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1=head1 NAME
2
3perldiag - various Perl diagnostics
4
5=head1 DESCRIPTION
6
7These messages are classified as follows (listed in increasing order of
8desperation):
9
10 (W) A warning (optional).
d1d15184 11 (D) A deprecation (enabled by default).
00eb3f2b 12 (S) A severe warning (enabled by default).
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13 (F) A fatal error (trappable).
14 (P) An internal error you should never see (trappable).
54310121 15 (X) A very fatal error (nontrappable).
cb1a09d0 16 (A) An alien error message (not generated by Perl).
a0d0e21e 17
75b44862 18The majority of messages from the first three classifications above
64977eb6 19(W, D & S) can be controlled using the C<warnings> pragma.
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20
21If a message can be controlled by the C<warnings> pragma, its warning
22category is included with the classification letter in the description
466416ed 23below. E.g. C<(W closed)> means a warning in the C<closed> category.
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24
25Optional warnings are enabled by using the C<warnings> pragma or the B<-w>
fa816bf3 26and B<-W> switches. Warnings may be captured by setting C<$SIG{__WARN__}>
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27to a reference to a routine that will be called on each warning instead
28of printing it. See L<perlvar>.
29
b7eceb5b 30Severe warnings are always enabled, unless they are explicitly disabled
e476b1b5 31with the C<warnings> pragma or the B<-X> switch.
4438c4b7 32
748a9306 33Trappable errors may be trapped using the eval operator. See
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34L<perlfunc/eval>. In almost all cases, warnings may be selectively
35disabled or promoted to fatal errors using the C<warnings> pragma.
36See L<warnings>.
a0d0e21e 37
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38The messages are in alphabetical order, without regard to upper or
39lower-case. Some of these messages are generic. Spots that vary are
40denoted with a %s or other printf-style escape. These escapes are
41ignored by the alphabetical order, as are all characters other than
42letters. To look up your message, just ignore anything that is not a
43letter.
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44
45=over 4
46
6df41af2 47=item accept() on closed socket %s
33633739 48
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49(W closed) You tried to do an accept on a closed socket. Did you forget
50to check the return value of your socket() call? See
51L<perlfunc/accept>.
33633739 52
de42a5a9 53=item Allocation too large: %x
a0d0e21e 54
6df41af2 55(X) You can't allocate more than 64K on an MS-DOS machine.
a0d0e21e 56
04f74579 57=item '%c' allowed only after types %s in %s
ef54e1a4 58
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59(F) The modifiers '!', '<' and '>' are allowed in pack() or unpack() only
60after certain types. See L<perlfunc/pack>.
ef54e1a4 61
6df41af2 62=item Ambiguous call resolved as CORE::%s(), qualify as such or use &
43192e07 63
75b44862 64(W ambiguous) A subroutine you have declared has the same name as a Perl
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65keyword, and you have used the name without qualification for calling
66one or the other. Perl decided to call the builtin because the
67subroutine is not imported.
43192e07 68
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69To force interpretation as a subroutine call, either put an ampersand
70before the subroutine name, or qualify the name with its package.
71Alternatively, you can import the subroutine (or pretend that it's
72imported with the C<use subs> pragma).
43192e07 73
6df41af2 74To silently interpret it as the Perl operator, use the C<CORE::> prefix
496a33f5 75on the operator (e.g. C<CORE::log($x)>) or declare the subroutine
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76to be an object method (see L<perlsub/"Subroutine Attributes"> or
77L<attributes>).
43192e07 78
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79=item Ambiguous range in transliteration operator
80
81(F) You wrote something like C<tr/a-z-0//> which doesn't mean anything at
82all. To include a C<-> character in a transliteration, put it either
83first or last. (In the past, C<tr/a-z-0//> was synonymous with
84C<tr/a-y//>, which was probably not what you would have expected.)
85
6df41af2 86=item Ambiguous use of %s resolved as %s
43192e07 87
7c7af292 88(S ambiguous) You said something that may not be interpreted the way
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89you thought. Normally it's pretty easy to disambiguate it by supplying
90a missing quote, operator, parenthesis pair or declaration.
a0d0e21e 91
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92=item Ambiguous use of -%s resolved as -&%s()
93
94(S ambiguous) You wrote something like C<-foo>, which might be the
95string C<"-foo">, or a call to the function C<foo>, negated. If you meant
96the string, just write C<"-foo">. If you meant the function call,
97write C<-foo()>.
98
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99=item Ambiguous use of %c resolved as operator %c
100
7c7af292 101(S ambiguous) C<%>, C<&>, and C<*> are both infix operators (modulus,
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102bitwise and, and multiplication) I<and> initial special characters
103(denoting hashes, subroutines and typeglobs), and you said something
104like C<*foo * foo> that might be interpreted as either of them. We
105assumed you meant the infix operator, but please try to make it more
106clear -- in the example given, you might write C<*foo * foo()> if you
107really meant to multiply a glob by the result of calling a function.
d8225693 108
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109=item Ambiguous use of %c{%s} resolved to %c%s
110
111(W ambiguous) You wrote something like C<@{foo}>, which might be
112asking for the variable C<@foo>, or it might be calling a function
113named foo, and dereferencing it as an array reference. If you wanted
1cecf2c0 114the variable, you can just write C<@foo>. If you wanted to call the
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115function, write C<@{foo()}> ... or you could just not have a variable
116and a function with the same name, and save yourself a lot of trouble.
117
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118=item Ambiguous use of %c{%s[...]} resolved to %c%s[...]
119
120=item Ambiguous use of %c{%s{...}} resolved to %c%s{...}
4da60377 121
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122(W ambiguous) You wrote something like C<${foo[2]}> (where foo represents
123the name of a Perl keyword), which might be looking for element number
1242 of the array named C<@foo>, in which case please write C<$foo[2]>, or you
125might have meant to pass an anonymous arrayref to the function named
126foo, and then do a scalar deref on the value it returns. If you meant
127that, write C<${foo([2])}>.
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128
129In regular expressions, the C<${foo[2]}> syntax is sometimes necessary
130to disambiguate between array subscripts and character classes.
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131C</$length[2345]/>, for instance, will be interpreted as C<$length> followed
132by the character class C<[2345]>. If an array subscript is what you
133want, you can avoid the warning by changing C</${length[2345]}/> to the
134unsightly C</${\$length[2345]}/>, by renaming your array to something
135that does not coincide with a built-in keyword, or by simply turning
136off warnings with C<no warnings 'ambiguous';>.
4da60377 137
6df41af2 138=item '|' and '<' may not both be specified on command line
a0d0e21e 139
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140(F) An error peculiar to VMS. Perl does its own command line
141redirection, and found that STDIN was a pipe, and that you also tried to
142redirect STDIN using '<'. Only one STDIN stream to a customer, please.
c9f97d15 143
6df41af2 144=item '|' and '>' may not both be specified on command line
1028017a 145
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146(F) An error peculiar to VMS. Perl does its own command line
147redirection, and thinks you tried to redirect stdout both to a file and
148into a pipe to another command. You need to choose one or the other,
149though nothing's stopping you from piping into a program or Perl script
150which 'splits' output into two streams, such as
1028017a 151
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152 open(OUT,">$ARGV[0]") or die "Can't write to $ARGV[0]: $!";
153 while (<STDIN>) {
154 print;
155 print OUT;
156 }
157 close OUT;
c9f97d15 158
6df41af2 159=item Applying %s to %s will act on scalar(%s)
eb6e2d6f 160
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161(W misc) The pattern match (C<//>), substitution (C<s///>), and
162transliteration (C<tr///>) operators work on scalar values. If you apply
be771a83 163one of them to an array or a hash, it will convert the array or hash to
ac036724 164a scalar value (the length of an array, or the population info of a
165hash) and then work on that scalar value. This is probably not what
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166you meant to do. See L<perlfunc/grep> and L<perlfunc/map> for
167alternatives.
eb6e2d6f 168
6df41af2 169=item Arg too short for msgsnd
76cd736e 170
6df41af2 171(F) msgsnd() requires a string at least as long as sizeof(long).
76cd736e 172
f86702cc 173=item Argument "%s" isn't numeric%s
a0d0e21e 174
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175(W numeric) The indicated string was fed as an argument to an operator
176that expected a numeric value instead. If you're fortunate the message
177will identify which operator was so unfortunate.
a0d0e21e 178
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179=item Argument list not closed for PerlIO layer "%s"
180
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181(W layer) When pushing a layer with arguments onto the Perl I/O
182system you forgot the ) that closes the argument list. (Layers
183take care of transforming data between external and internal
184representations.) Perl stopped parsing the layer list at this
185point and did not attempt to push this layer. If your program
186didn't explicitly request the failing operation, it may be the
187result of the value of the environment variable PERLIO.
b4581f09 188
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189=item Array @%s missing the @ in argument %d of %s()
190
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191(D deprecated) Really old Perl let you omit the @ on array names in some
192spots. This is now heavily deprecated.
a0d0e21e 193
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194=item A sequence of multiple spaces in a charnames alias definition is deprecated
195
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196(D deprecated) You defined a character name which had multiple space
197characters in a row. Change them to single spaces. Usually these
198names are defined in the C<:alias> import argument to C<use charnames>, but
199they could be defined by a translator installed into C<$^H{charnames}>.
200See L<charnames/CUSTOM ALIASES>.
bd299e29 201
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202=item assertion botched: %s
203
21b5e840 204(X) The malloc package that comes with Perl had an internal failure.
a0d0e21e 205
0eacef8e 206=item Assertion %s failed: file "%s", line %d
a0d0e21e 207
21b5e840 208(X) A general assertion failed. The file in question must be examined.
a0d0e21e 209
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210=item Assigning non-zero to $[ is no longer possible
211
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212(F) When the "array_base" feature is disabled (e.g., under C<use v5.16;>)
213the special variable C<$[>, which is deprecated, is now a fixed zero value.
82122228 214
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215=item Assignment to both a list and a scalar
216
217(F) If you assign to a conditional operator, the 2nd and 3rd arguments
218must either both be scalars or both be lists. Otherwise Perl won't
219know which context to supply to the right side.
220
2393f1b9 221=item Attempt to access disallowed key '%s' in a restricted hash
1b1f1335 222
49293501 223(F) The failing code has attempted to get or set a key which is not in
2393f1b9 224the current set of allowed keys of a restricted hash.
49293501 225
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226=item Attempt to bless into a freed package
227
228(F) You wrote C<bless $foo> with one argument after somehow causing
229the current package to be freed. Perl cannot figure out what to
230do, so it throws up in hands in despair.
231
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232=item Attempt to bless into a reference
233
234(F) The CLASSNAME argument to the bless() operator is expected to be
57dedab9 235the name of the package to bless the resulting object into. You've
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236supplied instead a reference to something: perhaps you wrote
237
238 bless $self, $proto;
239
240when you intended
241
242 bless $self, ref($proto) || $proto;
243
244If you actually want to bless into the stringified version
245of the reference supplied, you need to stringify it yourself, for
246example by:
247
248 bless $self, "$proto";
249
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250=item Attempt to clear deleted array
251
252(S debugging) An array was assigned to when it was being freed.
253Freed values are not supposed to be visible to Perl code. This
254can also happen if XS code calls C<av_clear> from a custom magic
255callback on the array.
256
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257=item Attempt to delete disallowed key '%s' from a restricted hash
258
259(F) The failing code attempted to delete from a restricted hash a key
260which is not in its key set.
261
262=item Attempt to delete readonly key '%s' from a restricted hash
263
264(F) The failing code attempted to delete a key whose value has been
265declared readonly from a restricted hash.
266
de42a5a9 267=item Attempt to free non-arena SV: 0x%x
a0d0e21e 268
f84fe999 269(S internal) All SV objects are supposed to be allocated from arenas
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270that will be garbage collected on exit. An SV was discovered to be
271outside any of those arenas.
a0d0e21e 272
12578ffb 273=item Attempt to free nonexistent shared string '%s'%s
bbce6d69 274
f84fe999 275(S internal) Perl maintains a reference-counted internal table of
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276strings to optimize the storage and access of hash keys and other
277strings. This indicates someone tried to decrement the reference count
278of a string that can no longer be found in the table.
bbce6d69 279
7d5b40b4 280=item Attempt to free temp prematurely: SV 0x%x
a0d0e21e 281
f84fe999 282(S debugging) Mortalized values are supposed to be freed by the
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283free_tmps() routine. This indicates that something else is freeing the
284SV before the free_tmps() routine gets a chance, which means that the
285free_tmps() routine will be freeing an unreferenced scalar when it does
286try to free it.
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287
288=item Attempt to free unreferenced glob pointers
289
f84fe999 290(S internal) The reference counts got screwed up on symbol aliases.
a0d0e21e 291
7d5b40b4 292=item Attempt to free unreferenced scalar: SV 0x%x
a0d0e21e 293
8f7e4d2c 294(S internal) Perl went to decrement the reference count of a scalar to
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295see if it would go to 0, and discovered that it had already gone to 0
296earlier, and should have been freed, and in fact, probably was freed.
297This could indicate that SvREFCNT_dec() was called too many times, or
298that SvREFCNT_inc() was called too few times, or that the SV was
299mortalized when it shouldn't have been, or that memory has been
300corrupted.
a0d0e21e 301
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302=item Attempt to pack pointer to temporary value
303
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304(W pack) You tried to pass a temporary value (like the result of a
305function, or a computed expression) to the "p" pack() template. This
306means the result contains a pointer to a location that could become
307invalid anytime, even before the end of the current statement. Use
308literals or global values as arguments to the "p" pack() template to
309avoid this warning.
84902520 310
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311=item Attempt to reload %s aborted.
312
313(F) You tried to load a file with C<use> or C<require> that failed to
314compile once already. Perl will not try to compile this file again
315unless you delete its entry from %INC. See L<perlfunc/require> and
316L<perlvar/%INC>.
317
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318=item Attempt to set length of freed array
319
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320(W misc) You tried to set the length of an array which has
321been freed. You can do this by storing a reference to the
322scalar representing the last index of an array and later
323assigning through that reference. For example
1b20cd17
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324
325 $r = do {my @a; \$#a};
326 $$r = 503
327
b7a902f4 328=item Attempt to use reference as lvalue in substr
329
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330(W substr) You supplied a reference as the first argument to substr()
331used as an lvalue, which is pretty strange. Perhaps you forgot to
332dereference it first. See L<perlfunc/substr>.
b7a902f4 333
c32124fe
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334=item Attribute "locked" is deprecated
335
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336(D deprecated) You have used the attributes pragma to modify the
337"locked" attribute on a code reference. The :locked attribute is
338obsolete, has had no effect since 5005 threads were removed, and
339will be removed in a future release of Perl 5.
c32124fe 340
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341=item Attribute prototype(%s) discards earlier prototype attribute in same sub
342
343(W misc) A sub was declared as sub foo : prototype(A) : prototype(B) {}, for
344example. Since each sub can only have one prototype, the earlier
345declaration(s) are discarded while the last one is applied.
346
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347=item Attribute "unique" is deprecated
348
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349(D deprecated) You have used the attributes pragma to modify
350the "unique" attribute on an array, hash or scalar reference.
351The :unique attribute has had no effect since Perl 5.8.8, and
352will be removed in a future release of Perl 5.
f1a3ce43 353
ccce04a4
FC
354=item av_reify called on tied array
355
356(S debugging) This indicates that something went wrong and Perl got I<very>
357confused about C<@_> or C<@DB::args> being tied.
358
de42a5a9 359=item Bad arg length for %s, is %u, should be %d
a0d0e21e 360
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361(F) You passed a buffer of the wrong size to one of msgctl(), semctl()
362or shmctl(). In C parlance, the correct sizes are, respectively,
5f05dabc 363S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)>, and
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364S<sizeof(struct shmid_ds *)>.
365
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366=item Bad evalled substitution pattern
367
496a33f5 368(F) You've used the C</e> switch to evaluate the replacement for a
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369substitution, but perl found a syntax error in the code to evaluate,
370most likely an unexpected right brace '}'.
371
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372=item Bad filehandle: %s
373
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374(F) A symbol was passed to something wanting a filehandle, but the
375symbol has no filehandle associated with it. Perhaps you didn't do an
376open(), or did it in another package.
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377
378=item Bad free() ignored
379
be771a83 380(S malloc) An internal routine called free() on something that had never
fa816bf3 381been malloc()ed in the first place. Mandatory, but can be disabled by
9ea8bc6d 382setting environment variable C<PERL_BADFREE> to 0.
33c8a3fe 383
9ea8bc6d 384This message can be seen quite often with DB_File on systems with "hard"
6903afa2 385dynamic linking, like C<AIX> and C<OS/2>. It is a bug of C<Berkeley DB>
be771a83 386which is left unnoticed if C<DB> uses I<forgiving> system malloc().
a0d0e21e 387
aa689395 388=item Bad hash
389
390(P) One of the internal hash routines was passed a null HV pointer.
391
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392=item Badly placed ()'s
393
394(A) You've accidentally run your script through B<csh> instead
395of Perl. Check the #! line, or manually feed your script into
396Perl yourself.
397
a7cb8dae 398=item Bad name after %s
a0d0e21e 399
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400(F) You started to name a symbol by using a package prefix, and then
401didn't finish the symbol. In particular, you can't interpolate outside
402of quotes, so
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403
404 $var = 'myvar';
405 $sym = mypack::$var;
406
407is not the same as
408
409 $var = 'myvar';
410 $sym = "mypack::$var";
411
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412=item Bad plugin affecting keyword '%s'
413
414(F) An extension using the keyword plugin mechanism violated the
415plugin API.
416
4ad56ec9
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417=item Bad realloc() ignored
418
6903afa2
FC
419(S malloc) An internal routine called realloc() on something that
420had never been malloc()ed in the first place. Mandatory, but can
421be disabled by setting the environment variable C<PERL_BADFREE> to 1.
4ad56ec9 422
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423=item Bad symbol for array
424
425(P) An internal request asked to add an array entry to something that
426wasn't a symbol table entry.
427
4df3f177
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428=item Bad symbol for dirhandle
429
430(P) An internal request asked to add a dirhandle entry to something
431that wasn't a symbol table entry.
432
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433=item Bad symbol for filehandle
434
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435(P) An internal request asked to add a filehandle entry to something
436that wasn't a symbol table entry.
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437
438=item Bad symbol for hash
439
440(P) An internal request asked to add a hash entry to something that
441wasn't a symbol table entry.
442
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443=item Bareword found in conditional
444
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445(W bareword) The compiler found a bareword where it expected a
446conditional, which often indicates that an || or && was parsed as part
447of the last argument of the previous construct, for example:
34d09196
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448
449 open FOO || die;
450
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451It may also indicate a misspelled constant that has been interpreted as
452a bareword:
34d09196
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453
454 use constant TYPO => 1;
455 if (TYOP) { print "foo" }
456
457The C<strict> pragma is useful in avoiding such errors.
458
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459=item Bareword "%s" not allowed while "strict subs" in use
460
461(F) With "strict subs" in use, a bareword is only allowed as a
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462subroutine identifier, in curly brackets or to the left of the "=>"
463symbol. Perhaps you need to predeclare a subroutine?
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464
465=item Bareword "%s" refers to nonexistent package
466
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467(W bareword) You used a qualified bareword of the form C<Foo::>, but the
468compiler saw no other uses of that namespace before that point. Perhaps
469you need to predeclare a package?
6df41af2 470
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471=item BEGIN failed--compilation aborted
472
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473(F) An untrapped exception was raised while executing a BEGIN
474subroutine. Compilation stops immediately and the interpreter is
475exited.
a0d0e21e 476
68dc0745 477=item BEGIN not safe after errors--compilation aborted
478
479(F) Perl found a C<BEGIN {}> subroutine (or a C<use> directive, which
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480implies a C<BEGIN {}>) after one or more compilation errors had already
481occurred. Since the intended environment for the C<BEGIN {}> could not
482be guaranteed (due to the errors), and since subsequent code likely
483depends on its correct operation, Perl just gave up.
68dc0745 484
c782d7ee 485=item \%d better written as $%d
6df41af2 486
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487(W syntax) Outside of patterns, backreferences live on as variables.
488The use of backslashes is grandfathered on the right-hand side of a
489substitution, but stylistically it's better to use the variable form
490because other Perl programmers will expect it, and it works better if
491there are more than 9 backreferences.
6df41af2 492
252aa082
JH
493=item Binary number > 0b11111111111111111111111111111111 non-portable
494
e476b1b5 495(W portable) The binary number you specified is larger than 2**32-1
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JH
496(4294967295) and therefore non-portable between systems. See
497L<perlport> for more on portability concerns.
252aa082 498
69282e91 499=item bind() on closed socket %s
a0d0e21e 500
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501(W closed) You tried to do a bind on a closed socket. Did you forget to
502check the return value of your socket() call? See L<perlfunc/bind>.
a0d0e21e 503
c289d2f7
JH
504=item binmode() on closed filehandle %s
505
506(W unopened) You tried binmode() on a filehandle that was never opened.
4dcecea4 507Check your control flow and number of arguments.
c289d2f7 508
e0e4a6e3
FC
509=item "\b{" is deprecated; use "\b\{" or "\b[{]" instead in regex; marked
510by S<<-- HERE> in m/%s/
f866a7cd 511
e0e4a6e3
FC
512=item "\B{" is deprecated; use "\B\{" or "\B[{]" instead in regex; marked
513by S<<-- HERE> in m/%s/
f866a7cd 514
3c664d1a 515(D deprecated) Use of an unescaped "{" immediately following
a38411bc
FC
516a C<\b> or C<\B> is now deprecated so as to reserve its use for Perl
517itself in a future release. You can either precede the brace
518with a backslash, or enclose it in square brackets; the latter
519is the way to go if the pattern delimiters are C<{}>.
f866a7cd 520
c5a0f51a
JH
521=item Bit vector size > 32 non-portable
522
e476b1b5 523(W portable) Using bit vector sizes larger than 32 is non-portable.
c5a0f51a 524
043c750c 525=item Bizarre copy of %s
4633a7c4 526
be771a83 527(P) Perl detected an attempt to copy an internal value that is not
ab830aa0 528copiable.
4633a7c4 529
5a25739d
FC
530=item Bizarre SvTYPE [%d]
531
434f489b 532(P) When starting a new thread or returning values from a thread, Perl
5a25739d
FC
533encountered an invalid data type.
534
f675dbe5
CB
535=item Buffer overflow in prime_env_iter: %s
536
be771a83
GS
537(W internal) A warning peculiar to VMS. While Perl was preparing to
538iterate over %ENV, it encountered a logical name or symbol definition
539which was too long, so it was truncated to the string shown.
f675dbe5 540
a0d0e21e
LW
541=item Callback called exit
542
4929bf7b 543(F) A subroutine invoked from an external package via call_sv()
a0d0e21e
LW
544exited by calling exit.
545
6df41af2 546=item %s() called too early to check prototype
f675dbe5 547
be771a83
GS
548(W prototype) You've called a function that has a prototype before the
549parser saw a definition or declaration for it, and Perl could not check
550that the call conforms to the prototype. You need to either add an
551early prototype declaration for the subroutine in question, or move the
552subroutine definition ahead of the call to get proper prototype
553checking. Alternatively, if you are certain that you're calling the
554function correctly, you may put an ampersand before the name to avoid
555the warning. See L<perlsub>.
f675dbe5 556
56feebad
FC
557=item Calling POSIX::%s() is deprecated
558
559(D deprecated) You called a function whose use is deprecated. See
560the function's name in L<POSIX> for details.
561
49704364 562=item Cannot compress integer in pack
0258719b
NC
563
564(F) An argument to pack("w",...) was too large to compress. The BER
565compressed integer format can only be used with positive integers, and you
566attempted to compress Infinity or a very large number (> 1e308).
567See L<perlfunc/pack>.
568
49704364 569=item Cannot compress negative numbers in pack
0258719b
NC
570
571(F) An argument to pack("w",...) was negative. The BER compressed integer
572format can only be used with positive integers. See L<perlfunc/pack>.
573
5c1f4d79
NC
574=item Cannot convert a reference to %s to typeglob
575
6903afa2
FC
576(F) You manipulated Perl's symbol table directly, stored a reference
577in it, then tried to access that symbol via conventional Perl syntax.
578The access triggers Perl to autovivify that typeglob, but it there is
579no legal conversion from that type of reference to a typeglob.
5c1f4d79 580
4040665a 581=item Cannot copy to %s
ba2fdce6
NC
582
583(P) Perl detected an attempt to copy a value to an internal type that cannot
4dcecea4 584be directly assigned to.
ba2fdce6 585
b5d97229
RGS
586=item Cannot find encoding "%s"
587
588(S io) You tried to apply an encoding that did not exist to a filehandle,
589either with open() or binmode().
590
7355df7e
FC
591=item Cannot set tied @DB::args
592
593(F) C<caller> tried to set C<@DB::args>, but found it tied. Tying C<@DB::args>
594is not supported. (Before this error was added, it used to crash.)
595
ce65bc73
FC
596=item Cannot tie unreifiable array
597
598(P) You somehow managed to call C<tie> on an array that does not
599keep a reference count on its arguments and cannot be made to
600do so. Such arrays are not even supposed to be accessible to
601Perl code, but are only used internally.
602
96ebfdd7
RK
603=item Can only compress unsigned integers in pack
604
605(F) An argument to pack("w",...) was not an integer. The BER compressed
606integer format can only be used with positive integers, and you attempted
607to compress something else. See L<perlfunc/pack>.
608
a0d0e21e
LW
609=item Can't bless non-reference value
610
611(F) Only hard references may be blessed. This is how Perl "enforces"
612encapsulation of objects. See L<perlobj>.
613
dc57907a
RGS
614=item Can't "break" in a loop topicalizer
615
0d863452 616(F) You called C<break>, but you're in a C<foreach> block rather than
6903afa2 617a C<given> block. You probably meant to use C<next> or C<last>.
0d863452
RH
618
619=item Can't "break" outside a given block
dc57907a 620
0d863452
RH
621(F) You called C<break>, but you're not inside a C<given> block.
622
6df41af2
GS
623=item Can't call method "%s" on an undefined value
624
625(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
626object reference or package name contains an undefined value. Something
627like this will reproduce the error:
6df41af2
GS
628
629 $BADREF = undef;
630 process $BADREF 1,2,3;
631 $BADREF->process(1,2,3);
632
a0d0e21e
LW
633=item Can't call method "%s" on unblessed reference
634
54310121 635(F) A method call must know in what package it's supposed to run. It
be771a83
GS
636ordinarily finds this out from the object reference you supply, but you
637didn't supply an object reference in this case. A reference isn't an
638object reference until it has been blessed. See L<perlobj>.
a0d0e21e
LW
639
640=item Can't call method "%s" without a package or object reference
641
642(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
643object reference or package name contains an expression that returns a
644defined value which is neither an object reference nor a package name.
72b5445b
GS
645Something like this will reproduce the error:
646
647 $BADREF = 42;
648 process $BADREF 1,2,3;
649 $BADREF->process(1,2,3);
650
dfe378f1
FC
651=item Can't call mro_isa_changed_in() on anonymous symbol table
652
653(P) Perl got confused as to whether a hash was a plain hash or a
654symbol table hash when trying to update @ISA caches.
655
2bf7e7b2
FC
656=item Can't call mro_method_changed_in() on anonymous symbol table
657
658(F) An XS module tried to call C<mro_method_changed_in> on a hash that was
659not attached to the symbol table.
660
a0d0e21e
LW
661=item Can't chdir to %s
662
f703fc96 663(F) You called C<perl -x/foo/bar>, but F</foo/bar> is not a directory
a0d0e21e
LW
664that you can chdir to, possibly because it doesn't exist.
665
0545a864 666=item Can't check filesystem of script "%s" for nosuid
104d25b7 667
be771a83
GS
668(P) For some reason you can't check the filesystem of the script for
669nosuid.
104d25b7 670
22e74366 671=item Can't coerce %s to %s in %s
a0d0e21e
LW
672
673(F) Certain types of SVs, in particular real symbol table entries
55497cff 674(typeglobs), can't be forced to stop being what they are. So you can't
a0d0e21e
LW
675say things like:
676
677 *foo += 1;
678
679You CAN say
680
681 $foo = *foo;
682 $foo += 1;
683
684but then $foo no longer contains a glob.
685
0d863452 686=item Can't "continue" outside a when block
dc57907a 687
0d863452
RH
688(F) You called C<continue>, but you're not inside a C<when>
689or C<default> block.
690
a0d0e21e
LW
691=item Can't create pipe mailbox
692
be771a83
GS
693(P) An error peculiar to VMS. The process is suffering from exhausted
694quotas or other plumbing problems.
a0d0e21e 695
eb64745e
GS
696=item Can't declare %s in "%s"
697
30c282f6
NC
698(F) Only scalar, array, and hash variables may be declared as "my", "our" or
699"state" variables. They must have ordinary identifiers as names.
a0d0e21e 700
fc7debfb
FC
701=item Can't "default" outside a topicalizer
702
703(F) You have used a C<default> block that is neither inside a
704C<foreach> loop nor a C<given> block. (Note that this error is
705issued on exit from the C<default> block, so you won't get the
706error if you use an explicit C<continue>.)
707
6df41af2
GS
708=item Can't do inplace edit: %s is not a regular file
709
be771a83 710(S inplace) You tried to use the B<-i> switch on a special file, such as
df7075a8 711a file in /dev, a FIFO or an uneditable directory. The file was ignored.
6df41af2 712
a0d0e21e
LW
713=item Can't do inplace edit on %s: %s
714
be771a83
GS
715(S inplace) The creation of the new file failed for the indicated
716reason.
a0d0e21e 717
54310121 718=item Can't do inplace edit without backup
a0d0e21e 719
be771a83
GS
720(F) You're on a system such as MS-DOS that gets confused if you try
721reading from a deleted (but still opened) file. You have to say
722C<-i.bak>, or some such.
a0d0e21e 723
10f9c03d 724=item Can't do inplace edit: %s would not be unique
a0d0e21e 725
e476b1b5 726(S inplace) Your filesystem does not support filenames longer than 14
10f9c03d
CK
727characters and Perl was unable to create a unique filename during
728inplace editing with the B<-i> switch. The file was ignored.
a0d0e21e 729
a0d0e21e
LW
730=item Can't do waitpid with flags
731
be771a83
GS
732(F) This machine doesn't have either waitpid() or wait4(), so only
733waitpid() without flags is emulated.
a0d0e21e 734
a0d0e21e
LW
735=item Can't emulate -%s on #! line
736
be771a83
GS
737(F) The #! line specifies a switch that doesn't make sense at this
738point. For example, it'd be kind of silly to put a B<-x> on the #!
739line.
a0d0e21e 740
1109a392
MHM
741=item Can't %s %s-endian %ss on this platform
742
743(F) Your platform's byte-order is neither big-endian nor little-endian,
744or it has a very strange pointer size. Packing and unpacking big- or
745little-endian floating point values and pointers may not be possible.
746See L<perlfunc/pack>.
747
a0d0e21e
LW
748=item Can't exec "%s": %s
749
d1be9408 750(W exec) A system(), exec(), or piped open call could not execute the
be771a83
GS
751named program for the indicated reason. Typical reasons include: the
752permissions were wrong on the file, the file wasn't found in
753C<$ENV{PATH}>, the executable in question was compiled for another
754architecture, or the #! line in a script points to an interpreter that
755can't be run for similar reasons. (Or maybe your system doesn't support
756#! at all.)
a0d0e21e
LW
757
758=item Can't exec %s
759
be771a83
GS
760(F) Perl was trying to execute the indicated program for you because
761that's what the #! line said. If that's not what you wanted, you may
762need to mention "perl" on the #! line somewhere.
a0d0e21e
LW
763
764=item Can't execute %s
765
be771a83
GS
766(F) You used the B<-S> switch, but the copies of the script to execute
767found in the PATH did not have correct permissions.
2a92aaa0 768
6df41af2 769=item Can't find an opnumber for "%s"
2a92aaa0 770
be771a83
GS
771(F) A string of a form C<CORE::word> was given to prototype(), but there
772is no builtin with the name C<word>.
6df41af2 773
56ca2fc0
JH
774=item Can't find %s character property "%s"
775
776(F) You used C<\p{}> or C<\P{}> but the character property by that name
6903afa2 777could not be found. Maybe you misspelled the name of the property?
e1b711da 778See L<perluniprops/Properties accessible through \p{} and \P{}>
9b73678d 779for a complete list of available official properties.
56ca2fc0 780
6df41af2
GS
781=item Can't find label %s
782
be771a83
GS
783(F) You said to goto a label that isn't mentioned anywhere that it's
784possible for us to go to. See L<perlfunc/goto>.
2a92aaa0
GS
785
786=item Can't find %s on PATH
787
be771a83
GS
788(F) You used the B<-S> switch, but the script to execute could not be
789found in the PATH.
a0d0e21e 790
6df41af2 791=item Can't find %s on PATH, '.' not in PATH
a0d0e21e 792
be771a83
GS
793(F) You used the B<-S> switch, but the script to execute could not be
794found in the PATH, or at least not with the correct permissions. The
795script exists in the current directory, but PATH prohibits running it.
a0d0e21e
LW
796
797=item Can't find string terminator %s anywhere before EOF
798
be771a83
GS
799(F) Perl strings can stretch over multiple lines. This message means
800that the closing delimiter was omitted. Because bracketed quotes count
801nesting levels, the following is missing its final parenthesis:
a0d0e21e 802
fb73857a 803 print q(The character '(' starts a side comment.);
804
97b3d10f 805If you're getting this error from a here-document, you may have
b6b8cb97
FC
806included unseen whitespace before or after your closing tag or there
807may not be a linebreak after it. A good programmer's editor will have
808a way to help you find these characters (or lack of characters). See
809L<perlop> for the full details on here-documents.
a0d0e21e 810
660a4616
TS
811=item Can't find Unicode property definition "%s"
812
5f8ad6b6
FC
813(F) You may have tried to use C<\p> which means a Unicode
814property (for example C<\p{Lu}> matches all uppercase
fa816bf3 815letters). If you did mean to use a Unicode property, see
e1b711da 816L<perluniprops/Properties accessible through \p{} and \P{}>
6903afa2 817for a complete list of available properties. If you didn't
fa816bf3
FC
818mean to use a Unicode property, escape the C<\p>, either by
819C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, or
5f8ad6b6 820until C<\E>).
660a4616 821
b3647a36 822=item Can't fork: %s
a0d0e21e 823
be771a83
GS
824(F) A fatal error occurred while trying to fork while opening a
825pipeline.
a0d0e21e 826
b3647a36
SR
827=item Can't fork, trying again in 5 seconds
828
c973c02e 829(W pipe) A fork in a piped open failed with EAGAIN and will be retried
b3647a36
SR
830after five seconds.
831
748a9306
LW
832=item Can't get filespec - stale stat buffer?
833
be771a83
GS
834(S) A warning peculiar to VMS. This arises because of the difference
835between access checks under VMS and under the Unix model Perl assumes.
836Under VMS, access checks are done by filename, rather than by bits in
837the stat buffer, so that ACLs and other protections can be taken into
838account. Unfortunately, Perl assumes that the stat buffer contains all
839the necessary information, and passes it, instead of the filespec, to
2fe2bdfd 840the access-checking routine. It will try to retrieve the filespec using
be771a83
GS
841the device name and FID present in the stat buffer, but this works only
842if you haven't made a subsequent call to the CRTL stat() routine,
843because the device name is overwritten with each call. If this warning
2fe2bdfd
FC
844appears, the name lookup failed, and the access-checking routine gave up
845and returned FALSE, just to be conservative. (Note: The access-checking
be771a83
GS
846routine knows about the Perl C<stat> operator and file tests, so you
847shouldn't ever see this warning in response to a Perl command; it arises
848only if some internal code takes stat buffers lightly.)
748a9306 849
a0d0e21e
LW
850=item Can't get pipe mailbox device name
851
be771a83
GS
852(P) An error peculiar to VMS. After creating a mailbox to act as a
853pipe, Perl can't retrieve its name for later use.
a0d0e21e
LW
854
855=item Can't get SYSGEN parameter value for MAXBUF
856
748a9306
LW
857(P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
858mailbox buffers to be, and didn't get an answer.
a0d0e21e 859
6df41af2 860=item Can't "goto" into the middle of a foreach loop
a0d0e21e 861
be771a83
GS
862(F) A "goto" statement was executed to jump into the middle of a foreach
863loop. You can't get there from here. See L<perlfunc/goto>.
6df41af2
GS
864
865=item Can't "goto" out of a pseudo block
866
be771a83
GS
867(F) A "goto" statement was executed to jump out of what might look like
868a block, except that it isn't a proper block. This usually occurs if
869you tried to jump out of a sort() block or subroutine, which is a no-no.
870See L<perlfunc/goto>.
a0d0e21e 871
5a25739d
FC
872=item Can't goto subroutine from an eval-%s
873
874(F) The "goto subroutine" call can't be used to jump out of an eval
875"string" or block.
876
9850bf21 877=item Can't goto subroutine from a sort sub (or similar callback)
cd299c6e 878
9850bf21
RH
879(F) The "goto subroutine" call can't be used to jump out of the
880comparison sub for a sort(), or from a similar callback (such
881as the reduce() function in List::Util).
882
6df41af2
GS
883=item Can't goto subroutine outside a subroutine
884
be771a83
GS
885(F) The deeply magical "goto subroutine" call can only replace one
886subroutine call for another. It can't manufacture one out of whole
887cloth. In general you should be calling it out of only an AUTOLOAD
888routine anyway. See L<perlfunc/goto>.
6df41af2 889
0b5b802d
GS
890=item Can't ignore signal CHLD, forcing to default
891
be771a83
GS
892(W signal) Perl has detected that it is being run with the SIGCHLD
893signal (sometimes known as SIGCLD) disabled. Since disabling this
894signal will interfere with proper determination of exit status of child
895processes, Perl has reset the signal to its default value. This
896situation typically indicates that the parent program under which Perl
897may be running (e.g. cron) is being very careless.
0b5b802d 898
e2c0f81f
DG
899=item Can't kill a non-numeric process ID
900
901(F) Process identifiers must be (signed) integers. It is a fatal error to
902attempt to kill() an undefined, empty-string or otherwise non-numeric
903process identifier.
904
6df41af2 905=item Can't "last" outside a loop block
4633a7c4 906
6df41af2 907(F) A "last" statement was executed to break out of the current block,
be771a83
GS
908except that there's this itty bitty problem called there isn't a current
909block. Note that an "if" or "else" block doesn't count as a "loopish"
910block, as doesn't a block given to sort(), map() or grep(). You can
911usually double the curlies to get the same effect though, because the
912inner curlies will be considered a block that loops once. See
913L<perlfunc/last>.
4633a7c4 914
2c7d6b9c
RGS
915=item Can't linearize anonymous symbol table
916
917(F) Perl tried to calculate the method resolution order (MRO) of a
918package, but failed because the package stash has no name.
919
b8170e59
JB
920=item Can't load '%s' for module %s
921
6903afa2
FC
922(F) The module you tried to load failed to load a dynamic extension.
923This may either mean that you upgraded your version of perl to one
924that is incompatible with your old dynamic extensions (which is known
925to happen between major versions of perl), or (more likely) that your
926dynamic extension was built against an older version of the library
927that is installed on your system. You may need to rebuild your old
928dynamic extensions.
b8170e59 929
748a9306
LW
930=item Can't localize lexical variable %s
931
2ba9eb46 932(F) You used local on a variable name that was previously declared as a
b7e4ecc1
FC
933lexical variable using "my" or "state". This is not allowed. If you
934want to localize a package variable of the same name, qualify it with
935the package name.
748a9306 936
6df41af2 937=item Can't localize through a reference
4727527e 938
6df41af2
GS
939(F) You said something like C<local $$ref>, which Perl can't currently
940handle, because when it goes to restore the old value of whatever $ref
be771a83 941pointed to after the scope of the local() is finished, it can't be sure
64977eb6 942that $ref will still be a reference.
4727527e 943
ea071790 944=item Can't locate %s
ec889f3a 945
fa816bf3
FC
946(F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be found.
947Perl looks for the file in all the locations mentioned in @INC, unless
948the file name included the full path to the file. Perhaps you need
949to set the PERL5LIB or PERL5OPT environment variable to say where the
950extra library is, or maybe the script needs to add the library name
be771a83
GS
951to @INC. Or maybe you just misspelled the name of the file. See
952L<perlfunc/require> and L<lib>.
a0d0e21e 953
6df41af2
GS
954=item Can't locate auto/%s.al in @INC
955
be771a83
GS
956(F) A function (or method) was called in a package which allows
957autoload, but there is no function to autoload. Most probable causes
958are a misprint in a function/method name or a failure to C<AutoSplit>
959the file, say, by doing C<make install>.
6df41af2 960
b8170e59
JB
961=item Can't locate loadable object for module %s in @INC
962
963(F) The module you loaded is trying to load an external library, like
d70d8e57 964for example, F<foo.so> or F<bar.dll>, but the L<DynaLoader> module was
b8170e59
JB
965unable to locate this library. See L<DynaLoader>.
966
a0d0e21e
LW
967=item Can't locate object method "%s" via package "%s"
968
969(F) You called a method correctly, and it correctly indicated a package
970functioning as a class, but that package doesn't define that particular
2ba9eb46 971method, nor does any of its base classes. See L<perlobj>.
a0d0e21e
LW
972
973=item Can't locate package %s for @%s::ISA
974
be771a83
GS
975(W syntax) The @ISA array contained the name of another package that
976doesn't seem to exist.
a0d0e21e 977
2f7da168
RK
978=item Can't locate PerlIO%s
979
980(F) You tried to use in open() a PerlIO layer that does not exist,
981e.g. open(FH, ">:nosuchlayer", "somefile").
982
f4ad53f4 983=item Can't make list assignment to %ENV on this system
3e3baf6d 984
be771a83
GS
985(F) List assignment to %ENV is not supported on some systems, notably
986VMS.
3e3baf6d 987
cd40cd58
NC
988=item Can't make loaded symbols global on this platform while loading %s
989
ff9c1ae8 990(S) A module passed the flag 0x01 to DynaLoader::dl_load_file() to request
cd40cd58
NC
991that symbols from the stated file are made available globally within the
992process, but that functionality is not available on this platform. Whilst
993the module likely will still work, this may prevent the perl interpreter
994from loading other XS-based extensions which need to link directly to
995functions defined in the C or XS code in the stated file.
996
a0d0e21e
LW
997=item Can't modify %s in %s
998
be771a83
GS
999(F) You aren't allowed to assign to the item indicated, or otherwise try
1000to change it, such as with an auto-increment.
a0d0e21e 1001
54310121 1002=item Can't modify nonexistent substring
a0d0e21e
LW
1003
1004(P) The internal routine that does assignment to a substr() was handed
1005a NULL.
1006
6df41af2
GS
1007=item Can't modify non-lvalue subroutine call
1008
1009(F) Subroutines meant to be used in lvalue context should be declared as
2fe2bdfd 1010such. See L<perlsub/"Lvalue subroutines">.
6df41af2 1011
5f05dabc 1012=item Can't msgrcv to read-only var
a0d0e21e 1013
5f05dabc 1014(F) The target of a msgrcv must be modifiable to be used as a receive
a0d0e21e
LW
1015buffer.
1016
6df41af2
GS
1017=item Can't "next" outside a loop block
1018
1019(F) A "next" statement was executed to reiterate the current block, but
1020there isn't a current block. Note that an "if" or "else" block doesn't
be771a83
GS
1021count as a "loopish" block, as doesn't a block given to sort(), map() or
1022grep(). You can usually double the curlies to get the same effect
1023though, because the inner curlies will be considered a block that loops
1024once. See L<perlfunc/next>.
6df41af2 1025
46fa9b26
FC
1026=item Can't open %s
1027
1028(F) You tried to run a perl built with MAD support with
1029the PERL_XMLDUMP environment variable set, but the file
1030named by that variable could not be opened.
1031
a0d0e21e
LW
1032=item Can't open %s: %s
1033
c47ff5f1 1034(S inplace) The implicit opening of a file through use of the C<< <> >>
08e9d68e 1035filehandle, either implicitly under the C<-n> or C<-p> command-line
46fa9b26
FC
1036switches, or explicitly, failed for the indicated reason. Usually
1037this is because you don't have read permission for a file which
1038you named on the command line.
1039
1040(F) You tried to call perl with the B<-e> switch, but F</dev/null> (or
1041your operating system's equivalent) could not be opened.
a0d0e21e 1042
9a869a14
RGS
1043=item Can't open a reference
1044
1045(W io) You tried to open a scalar reference for reading or writing,
2fe2bdfd 1046using the 3-arg open() syntax:
9a869a14
RGS
1047
1048 open FH, '>', $ref;
1049
1050but your version of perl is compiled without perlio, and this form of
1051open is not supported.
1052
a0d0e21e
LW
1053=item Can't open bidirectional pipe
1054
be771a83
GS
1055(W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
1056You can try any of several modules in the Perl library to do this, such
1057as IPC::Open2. Alternately, direct the pipe's output to a file using
1058">", and then read it in under a different file handle.
a0d0e21e 1059
748a9306
LW
1060=item Can't open error file %s as stderr
1061
be771a83
GS
1062(F) An error peculiar to VMS. Perl does its own command line
1063redirection, and couldn't open the file specified after '2>' or '2>>' on
1064the command line for writing.
748a9306
LW
1065
1066=item Can't open input file %s as stdin
1067
be771a83
GS
1068(F) An error peculiar to VMS. Perl does its own command line
1069redirection, and couldn't open the file specified after '<' on the
1070command line for reading.
748a9306
LW
1071
1072=item Can't open output file %s as stdout
1073
be771a83
GS
1074(F) An error peculiar to VMS. Perl does its own command line
1075redirection, and couldn't open the file specified after '>' or '>>' on
1076the command line for writing.
748a9306
LW
1077
1078=item Can't open output pipe (name: %s)
1079
be771a83
GS
1080(P) An error peculiar to VMS. Perl does its own command line
1081redirection, and couldn't open the pipe into which to send data destined
1082for stdout.
748a9306 1083
3b1cf97d 1084=item Can't open perl script "%s": %s
a0d0e21e
LW
1085
1086(F) The script you specified can't be opened for the indicated reason.
1087
fa3aa65a
JC
1088If you're debugging a script that uses #!, and normally relies on the
1089shell's $PATH search, the -S option causes perl to do that search, so
1090you don't have to type the path or C<`which $scriptname`>.
1091
6df41af2
GS
1092=item Can't read CRTL environ
1093
1094(S) A warning peculiar to VMS. Perl tried to read an element of %ENV
1095from the CRTL's internal environment array and discovered the array was
1096missing. You need to figure out where your CRTL misplaced its environ
be771a83
GS
1097or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
1098searched.
6df41af2 1099
6df41af2
GS
1100=item Can't "redo" outside a loop block
1101
1102(F) A "redo" statement was executed to restart the current block, but
1103there isn't a current block. Note that an "if" or "else" block doesn't
1104count as a "loopish" block, as doesn't a block given to sort(), map()
1105or grep(). You can usually double the curlies to get the same effect
1106though, because the inner curlies will be considered a block that
1107loops once. See L<perlfunc/redo>.
1108
64977eb6 1109=item Can't remove %s: %s, skipping file
10f9c03d 1110
be771a83
GS
1111(S inplace) You requested an inplace edit without creating a backup
1112file. Perl was unable to remove the original file to replace it with
1113the modified file. The file was left unmodified.
10f9c03d 1114
a0d0e21e
LW
1115=item Can't rename %s to %s: %s, skipping file
1116
e476b1b5 1117(S inplace) The rename done by the B<-i> switch failed for some reason,
10f9c03d 1118probably because you don't have write permission to the directory.
a0d0e21e 1119
748a9306
LW
1120=item Can't reopen input pipe (name: %s) in binary mode
1121
be771a83
GS
1122(P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
1123to reopen it to accept binary data. Alas, it failed.
748a9306 1124
4f12ec0e
FC
1125=item Can't reset %ENV on this system
1126
1127(F) You called C<reset('E')> or similar, which tried to reset
1128all variables in the current package beginning with "E". In
1129the main package, that includes %ENV. Resetting %ENV is not
1130supported on some systems, notably VMS.
1131
fe13d51d 1132=item Can't resolve method "%s" overloading "%s" in package "%s"
6df41af2 1133
1fa582fa
FC
1134(F)(P) Error resolving overloading specified by a method name (as
1135opposed to a subroutine reference): no such method callable via the
1136package. If the method name is C<???>, this is an internal error.
6df41af2 1137
cd06dffe
GS
1138=item Can't return %s from lvalue subroutine
1139
be771a83
GS
1140(F) Perl detected an attempt to return illegal lvalues (such as
1141temporary or readonly values) from a subroutine used as an lvalue. This
1142is not allowed.
cd06dffe 1143
96ebfdd7
RK
1144=item Can't return outside a subroutine
1145
1146(F) The return statement was executed in mainline code, that is, where
1147there was no subroutine call to return out of. See L<perlsub>.
1148
78f9721b
SM
1149=item Can't return %s to lvalue scalar context
1150
6903afa2
FC
1151(F) You tried to return a complete array or hash from an lvalue
1152subroutine, but you called the subroutine in a way that made Perl
1153think you meant to return only one value. You probably meant to
1154write parentheses around the call to the subroutine, which tell
1155Perl that the call should be in list context.
78f9721b 1156
a0d0e21e
LW
1157=item Can't stat script "%s"
1158
be771a83
GS
1159(P) For some reason you can't fstat() the script even though you have it
1160open already. Bizarre.
a0d0e21e 1161
a0d0e21e
LW
1162=item Can't take log of %g
1163
fb73857a 1164(F) For ordinary real numbers, you can't take the logarithm of a
6903afa2 1165negative number or zero. There's a Math::Complex package that comes
be771a83
GS
1166standard with Perl, though, if you really want to do that for the
1167negative numbers.
a0d0e21e
LW
1168
1169=item Can't take sqrt of %g
1170
1171(F) For ordinary real numbers, you can't take the square root of a
fb73857a 1172negative number. There's a Math::Complex package that comes standard
1173with Perl, though, if you really want to do that.
a0d0e21e
LW
1174
1175=item Can't undef active subroutine
1176
1177(F) You can't undefine a routine that's currently running. You can,
1178however, redefine it while it's running, and you can even undef the
1179redefined subroutine while the old routine is running. Go figure.
1180
c81225bc 1181=item Can't upgrade %s (%d) to %d
a0d0e21e 1182
be771a83
GS
1183(P) The internal sv_upgrade routine adds "members" to an SV, making it
1184into a more specialized kind of SV. The top several SV types are so
1185specialized, however, that they cannot be interconverted. This message
1186indicates that such a conversion was attempted.
a0d0e21e 1187
6651ba0b
FC
1188=item Can't use '%c' after -mname
1189
1190(F) You tried to call perl with the B<-m> switch, but you put something
1191other than "=" after the module name.
1192
1db89ea5
BS
1193=item Can't use anonymous symbol table for method lookup
1194
e27ad1f2 1195(F) The internal routine that does method lookup was handed a symbol
1db89ea5
BS
1196table that doesn't have a name. Symbol tables can become anonymous
1197for example by undefining stashes: C<undef %Some::Package::>.
1198
96ebfdd7
RK
1199=item Can't use an undefined value as %s reference
1200
1201(F) A value used as either a hard reference or a symbolic reference must
1202be a defined value. This helps to delurk some insidious errors.
1203
6df41af2
GS
1204=item Can't use bareword ("%s") as %s ref while "strict refs" in use
1205
be771a83
GS
1206(F) Only hard references are allowed by "strict refs". Symbolic
1207references are disallowed. See L<perlref>.
6df41af2 1208
90b75b61 1209=item Can't use %! because Errno.pm is not available
1d2dff63 1210
20561843 1211(F) The first time the C<%!> hash is used, perl automatically loads the
6903afa2 1212Errno.pm module. The Errno module is expected to tie the %! hash to
1d2dff63
GS
1213provide symbolic names for C<$!> errno values.
1214
1109a392
MHM
1215=item Can't use both '<' and '>' after type '%c' in %s
1216
1217(F) A type cannot be forced to have both big-endian and little-endian
1218byte-order at the same time, so this combination of modifiers is not
1219allowed. See L<perlfunc/pack>.
1220
6df41af2
GS
1221=item Can't use %s for loop variable
1222
be771a83
GS
1223(F) Only a simple scalar variable may be used as a loop variable on a
1224foreach.
6df41af2 1225
aab6a793 1226=item Can't use global %s in "%s"
6df41af2 1227
be771a83
GS
1228(F) You tried to declare a magical variable as a lexical variable. This
1229is not allowed, because the magic can be tied to only one location
1230(namely the global variable) and it would be incredibly confusing to
1231have variables in your program that looked like magical variables but
6df41af2
GS
1232weren't.
1233
6d3b25aa
RGS
1234=item Can't use '%c' in a group with different byte-order in %s
1235
1236(F) You attempted to force a different byte-order on a type
1237that is already inside a group with a byte-order modifier.
1238For example you cannot force little-endianness on a type that
1239is inside a big-endian group.
1240
c07a80fd 1241=item Can't use "my %s" in sort comparison
1242
1243(F) The global variables $a and $b are reserved for sort comparisons.
c47ff5f1 1244You mentioned $a or $b in the same line as the <=> or cmp operator,
c07a80fd 1245and the variable had earlier been declared as a lexical variable.
1246Either qualify the sort variable with the package name, or rename the
1247lexical variable.
1248
a0d0e21e
LW
1249=item Can't use %s ref as %s ref
1250
1251(F) You've mixed up your reference types. You have to dereference a
1252reference of the type needed. You can use the ref() function to
1253test the type of the reference, if need be.
1254
748a9306 1255=item Can't use string ("%s") as %s ref while "strict refs" in use
a0d0e21e 1256
5e634d20
FC
1257=item Can't use string ("%s"...) as %s ref while "strict refs" in use
1258
b41bf23f
FC
1259(F) You've told Perl to dereference a string, something which
1260C<use strict> blocks to prevent it happening accidentally. See
1261L<perlref/"Symbolic references">. This can be triggered by an C<@> or C<$>
1262in a double-quoted string immediately before interpolating a variable,
1263for example in C<"user @$twitter_id">, which says to treat the contents
1264of C<$twitter_id> as an array reference; use a C<\> to have a literal C<@>
1265symbol followed by the contents of C<$twitter_id>: C<"user \@$twitter_id">.
a0d0e21e 1266
748a9306
LW
1267=item Can't use subscript on %s
1268
1269(F) The compiler tried to interpret a bracketed expression as a
1270subscript. But to the left of the brackets was an expression that
209e7cf1 1271didn't look like a hash or array reference, or anything else subscriptable.
748a9306 1272
6df41af2
GS
1273=item Can't use \%c to mean $%c in expression
1274
75b44862
GS
1275(W syntax) In an ordinary expression, backslash is a unary operator that
1276creates a reference to its argument. The use of backslash to indicate a
1277backreference to a matched substring is valid only as part of a regular
be771a83
GS
1278expression pattern. Trying to do this in ordinary Perl code produces a
1279value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1280instead.
6df41af2 1281
810b8aa5
GS
1282=item Can't weaken a nonreference
1283
1284(F) You attempted to weaken something that was not a reference. Only
1285references can be weakened.
1286
fc7debfb
FC
1287=item Can't "when" outside a topicalizer
1288
1289(F) You have used a when() block that is neither inside a C<foreach>
1290loop nor a C<given> block. (Note that this error is issued on exit
1291from the C<when> block, so you won't get the error if the match fails,
1292or if you use an explicit C<continue>.)
1293
5f05dabc 1294=item Can't x= to read-only value
a0d0e21e 1295
be771a83
GS
1296(F) You tried to repeat a constant value (often the undefined value)
1297with an assignment operator, which implies modifying the value itself.
a0d0e21e
LW
1298Perhaps you need to copy the value to a temporary, and repeat that.
1299
a04e6aad 1300=item Character following "\c" must be printable ASCII
f9d13529 1301
a04e6aad
KW
1302(F)(D deprecated, syntax) In C<\cI<X>>, I<X> must be a printable
1303(non-control) ASCII character. This is fatal starting in v5.20 for
1304non-ASCII characters, and it is planned to make this fatal in all
1305instances in Perl v5.22. In
675fa9ff 1306the cases where it isn't fatal, the character this evaluates to is
17a3df4c
KW
1307derived by exclusive or'ing the code point of this character with 0x40.
1308
727b6379
KW
1309Note that ASCII characters that don't map to control characters are
1310discouraged here as well, and will generate the warning (when enabled)
1311L</""\c%c" is more clearly written simply as "%s"">.
f9d13529 1312
f337b084 1313=item Character in 'C' format wrapped in pack
ac7cd81a
SC
1314
1315(W pack) You said
1316
1317 pack("C", $x)
1318
1319where $x is either less than 0 or more than 255; the C<"C"> format is
1320only for encoding native operating system characters (ASCII, EBCDIC,
1321and so on) and not for Unicode characters, so Perl behaved as if you meant
1322
1323 pack("C", $x & 255)
1324
1325If you actually want to pack Unicode codepoints, use the C<"U"> format
1326instead.
1327
f337b084 1328=item Character in 'c' format wrapped in pack
ac7cd81a
SC
1329
1330(W pack) You said
1331
1332 pack("c", $x)
1333
1334where $x is either less than -128 or more than 127; the C<"c"> format
1335is only for encoding native operating system characters (ASCII, EBCDIC,
1336and so on) and not for Unicode characters, so Perl behaved as if you meant
1337
1338 pack("c", $x & 255);
1339
1340If you actually want to pack Unicode codepoints, use the C<"U"> format
1341instead.
1342
f337b084
TH
1343=item Character in '%c' format wrapped in unpack
1344
1345(W unpack) You tried something like
1346
1347 unpack("H", "\x{2a1}")
1348
1a147d38 1349where the format expects to process a byte (a character with a value
6903afa2
FC
1350below 256), but a higher value was provided instead. Perl uses the
1351value modulus 256 instead, as if you had provided:
f337b084
TH
1352
1353 unpack("H", "\x{a1}")
1354
5a25739d
FC
1355=item Character in 'W' format wrapped in pack
1356
1357(W pack) You said
1358
1359 pack("U0W", $x)
1360
1361where $x is either less than 0 or more than 255. However, C<U0>-mode
1362expects all values to fall in the interval [0, 255], so Perl behaved
1363as if you meant:
1364
1365 pack("U0W", $x & 255)
1366
f337b084
TH
1367=item Character(s) in '%c' format wrapped in pack
1368
1369(W pack) You tried something like
1370
1371 pack("u", "\x{1f3}b")
1372
1a147d38 1373where the format expects to process a sequence of bytes (character with a
6903afa2 1374value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1375uses the character values modulus 256 instead, as if you had provided:
1376
1377 pack("u", "\x{f3}b")
1378
1379=item Character(s) in '%c' format wrapped in unpack
1380
1381(W unpack) You tried something like
1382
1383 unpack("s", "\x{1f3}b")
1384
1a147d38 1385where the format expects to process a sequence of bytes (character with a
6903afa2 1386value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1387uses the character values modulus 256 instead, as if you had provided:
1388
1389 unpack("s", "\x{f3}b")
1390
f866a7cd
FC
1391=item "\c%c" is more clearly written simply as "%s"
1392
1393(W syntax) The C<\cI<X>> construct is intended to be a way to specify
1394non-printable characters. You used it for a printable one, which is better
1395written as simply itself, perhaps preceded by a backslash for non-word
1396characters.
1397
6651ba0b
FC
1398=item Cloning substitution context is unimplemented
1399
1400(F) Creating a new thread inside the C<s///> operator is not supported.
1401
abc7ecad
SP
1402=item closedir() attempted on invalid dirhandle %s
1403
1404(W io) The dirhandle you tried to close is either closed or not really
1405a dirhandle. Check your control flow.
1406
5a25739d
FC
1407=item close() on unopened filehandle %s
1408
1409(W unopened) You tried to close a filehandle that was never opened.
1410
541ed3a9
FC
1411=item Closure prototype called
1412
1413(F) If a closure has attributes, the subroutine passed to an attribute
1414handler is the prototype that is cloned when a new closure is created.
1415This subroutine cannot be called.
1416
49704364
WL
1417=item Code missing after '/'
1418
6903afa2
FC
1419(F) You had a (sub-)template that ends with a '/'. There must be
1420another template code following the slash. See L<perlfunc/pack>.
49704364 1421
5a25739d
FC
1422=item Code point 0x%X is not Unicode, may not be portable
1423
2d88a86a 1424(S non_unicode) You had a code point above the Unicode maximum
1b64326b
FC
1425of U+10FFFF.
1426
1427Perl allows strings to contain a superset of Unicode code points, up
1428to the limit of what is storable in an unsigned integer on your system,
1429but these may not be accepted by other languages/systems. At one time,
1430it was legal in some standards to have code points up to 0x7FFF_FFFF,
1431but not higher. Code points above 0xFFFF_FFFF require larger than a
143232 bit word.
0876b9a0 1433
6df41af2
GS
1434=item %s: Command not found
1435
a892b81a 1436(A) You've accidentally run your script through B<csh> or another shell
f738a371 1437instead of Perl. Check the #! line, or manually feed your script
a892b81a 1438into Perl yourself. The #! line at the top of your file could look like
8f721816
MM
1439
1440 #!/usr/bin/perl -w
6df41af2 1441
7a2e2cd6 1442=item Compilation failed in require
1443
1444(F) Perl could not compile a file specified in a C<require> statement.
be771a83
GS
1445Perl uses this generic message when none of the errors that it
1446encountered were severe enough to halt compilation immediately.
7a2e2cd6 1447
c3464db5
DD
1448=item Complex regular subexpression recursion limit (%d) exceeded
1449
be771a83
GS
1450(W regexp) The regular expression engine uses recursion in complex
1451situations where back-tracking is required. Recursion depth is limited
1452to 32766, or perhaps less in architectures where the stack cannot grow
1453arbitrarily. ("Simple" and "medium" situations are handled without
1454recursion and are not subject to a limit.) Try shortening the string
1455under examination; looping in Perl code (e.g. with C<while>) rather than
1456in the regular expression engine; or rewriting the regular expression so
c2e66d9e 1457that it is simpler or backtracks less. (See L<perlfaq2> for information
be771a83 1458on I<Mastering Regular Expressions>.)
c3464db5 1459
69282e91 1460=item connect() on closed socket %s
a0d0e21e 1461
be771a83
GS
1462(W closed) You tried to do a connect on a closed socket. Did you forget
1463to check the return value of your socket() call? See
1464L<perlfunc/connect>.
a0d0e21e 1465
e21e7c6a
FC
1466=item Constant(%s): Call to &{$^H{%s}} did not return a defined value
1467
1468(F) The subroutine registered to handle constant overloading
1469(see L<overload>) or a custom charnames handler (see
1470L<charnames/CUSTOM TRANSLATORS>) returned an undefined value.
1471
1472=item Constant(%s): $^H{%s} is not defined
1473
1474(F) The parser found inconsistencies while attempting to define an
1475overloaded constant. Perhaps you forgot to load the corresponding
f738a371 1476L<overload> pragma?
e21e7c6a 1477
779c5bc9
GS
1478=item Constant is not %s reference
1479
1480(F) A constant value (perhaps declared using the C<use constant> pragma)
be771a83 1481is being dereferenced, but it amounts to the wrong type of reference.
6903afa2 1482The message indicates the type of reference that was expected. This
be771a83 1483usually indicates a syntax error in dereferencing the constant value.
779c5bc9
GS
1484See L<perlsub/"Constant Functions"> and L<constant>.
1485
4cee8e80
CS
1486=item Constant subroutine %s redefined
1487
aeb94125
FC
1488(W redefine)(S) You redefined a subroutine which had previously
1489been eligible for inlining. See L<perlsub/"Constant Functions">
1490for commentary and workarounds.
4cee8e80 1491
9607fc9c 1492=item Constant subroutine %s undefined
1493
be771a83
GS
1494(W misc) You undefined a subroutine which had previously been eligible
1495for inlining. See L<perlsub/"Constant Functions"> for commentary and
1496workarounds.
9607fc9c 1497
5a25739d
FC
1498=item Constant(%s) unknown
1499
1500(F) The parser found inconsistencies either while attempting
1501to define an overloaded constant, or when trying to find the
1502character name specified in the C<\N{...}> escape. Perhaps you
1503forgot to load the corresponding L<overload> pragma?.
1504
e7ea3e70
IZ
1505=item Copy method did not return a reference
1506
6903afa2 1507(F) The method which overloads "=" is buggy. See
13a2d996 1508L<overload/Copy Constructor>.
e7ea3e70 1509
4aaa4757
FC
1510=item &CORE::%s cannot be called directly
1511
1512(F) You tried to call a subroutine in the C<CORE::> namespace
8d605c0d 1513with C<&foo> syntax or through a reference. Some subroutines
4aaa4757
FC
1514in this package cannot yet be called that way, but must be
1515called as barewords. Something like this will work:
1516
1517 BEGIN { *shove = \&CORE::push; }
1518 shove @array, 1,2,3; # pushes on to @array
1519
6798c92b
GS
1520=item CORE::%s is not a keyword
1521
1522(F) The CORE:: namespace is reserved for Perl keywords.
1523
675fa9ff
FC
1524=item Corrupted regexp opcode %d > %d
1525
1526(P) This is either an error in Perl, or, if you're using
1527one, your L<custom regular expression engine|perlreapi>. If not the
1528latter, report the problem through the L<perlbug> utility.
1529
a0d0e21e
LW
1530=item corrupted regexp pointers
1531
1532(P) The regular expression engine got confused by what the regular
1533expression compiler gave it.
1534
1535=item corrupted regexp program
1536
be771a83
GS
1537(P) The regular expression engine got passed a regexp program without a
1538valid magic number.
a0d0e21e 1539
de42a5a9 1540=item Corrupt malloc ptr 0x%x at 0x%x
6df41af2
GS
1541
1542(P) The malloc package that comes with Perl had an internal failure.
1543
49704364
WL
1544=item Count after length/code in unpack
1545
1546(F) You had an unpack template indicating a counted-length string, but
1547you have also specified an explicit size for the string. See
1548L<perlfunc/pack>.
1549
f2cccb4c
KW
1550=for comment
1551The following are used in lib/diagnostics.t for testing two =items that
1552share the same description. Changes here need to be propagated to there
1553
6651ba0b
FC
1554=item Deep recursion on anonymous subroutine
1555
a0d0e21e
LW
1556=item Deep recursion on subroutine "%s"
1557
be771a83
GS
1558(W recursion) This subroutine has called itself (directly or indirectly)
1559100 times more than it has returned. This probably indicates an
1560infinite recursion, unless you're writing strange benchmark programs, in
1561which case it indicates something else.
a0d0e21e 1562
aad1d01f
NC
1563This threshold can be changed from 100, by recompiling the F<perl> binary,
1564setting the C pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1565
f10b0346 1566=item defined(@array) is deprecated
69794302 1567
be771a83
GS
1568(D deprecated) defined() is not usually useful on arrays because it
1569checks for an undefined I<scalar> value. If you want to see if the
64977eb6 1570array is empty, just use C<if (@array) { # not empty }> for example.
69794302 1571
f10b0346 1572=item defined(%hash) is deprecated
69794302 1573
f0ec9725
KR
1574(D deprecated) C<defined()> is not usually right on hashes and has been
1575discouraged since 5.004.
1576
1577Although C<defined %hash> is false on a plain not-yet-used hash, it
1578becomes true in several non-obvious circumstances, including iterators,
1579weak references, stash names, even remaining true after C<undef %hash>.
1580These things make C<defined %hash> fairly useless in practice.
1581
1582If a check for non-empty is what you wanted then just put it in boolean
1583context (see L<perldata/Scalar values>):
16546e45
KR
1584
1585 if (%hash) {
1586 # not empty
1587 }
1588
f0ec9725
KR
1589If you had C<defined %Foo::Bar::QUUX> to check whether such a package
1590variable exists then that's never really been reliable, and isn't
1591a good way to enquire about the features of a package, or whether
1592it's loaded, etc.
1593
69794302 1594
e0e4a6e3
FC
1595=item (?(DEFINE)....) does not allow branches in regex; marked by
1596S<<-- HERE> in m/%s/
bcb95744 1597
6903afa2 1598(F) You used something like C<(?(DEFINE)...|..)> which is illegal. The
bcb95744
FC
1599most likely cause of this error is that you left out a parenthesis inside
1600of the C<....> part.
1601
9e3ec65c 1602The <-- HERE shows whereabouts in the regular expression the problem was
bcb95744
FC
1603discovered.
1604
62658f4d
PM
1605=item %s defines neither package nor VERSION--version check failed
1606
1607(F) You said something like "use Module 42" but in the Module file
1608there are neither package declarations nor a C<$VERSION>.
1609
36447869
FC
1610=item delete argument is index/value array slice, use array slice
1611
1612(F) You used index/value array slice syntax (C<%array[...]>) as
1613the argument to C<delete>. You probably meant C<@array[...]> with
1614an @ symbol instead.
1615
1616=item delete argument is key/value hash slice, use hash slice
1617
1618(F) You used key/value hash slice syntax (C<%hash{...}>) as the argument to
1619C<delete>. You probably meant C<@hash{...}> with an @ symbol instead.
1620
0ffcbc25
FC
1621=item delete argument is not a HASH or ARRAY element or slice
1622
4a0af295 1623(F) The argument to C<delete> must be either a hash or array element,
0ffcbc25
FC
1624such as:
1625
1626 $foo{$bar}
1627 $ref->{"susie"}[12]
1628
1629or a hash or array slice, such as:
1630
1631 @foo[$bar, $baz, $xyzzy]
1632 @{$ref->[12]}{"susie", "queue"}
1633
fc36a67e 1634=item Delimiter for here document is too long
1635
be771a83
GS
1636(F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1637long for Perl to handle. You have to be seriously twisted to write code
1638that triggers this error.
fc36a67e 1639
6d3b25aa
RGS
1640=item Deprecated use of my() in false conditional
1641
fa816bf3
FC
1642(D deprecated) You used a declaration similar to C<my $x if 0>. There
1643has been a long-standing bug in Perl that causes a lexical variable
6d3b25aa 1644not to be cleared at scope exit when its declaration includes a false
6903afa2 1645conditional. Some people have exploited this bug to achieve a kind of
fa816bf3 1646static variable. Since we intend to fix this bug, we don't want people
6903afa2 1647relying on this behavior. You can achieve a similar static effect by
6d3b25aa 1648declaring the variable in a separate block outside the function, eg
36fb85f3 1649
6d3b25aa
RGS
1650 sub f { my $x if 0; return $x++ }
1651
1652becomes
1653
1654 { my $x; sub f { return $x++ } }
1655
ea9d9ebc 1656Beginning with perl 5.10.0, you can also use C<state> variables to have
fa816bf3 1657lexicals that are initialized only once (see L<feature>):
36fb85f3
RGS
1658
1659 sub f { state $x; return $x++ }
1660
500ab966
RGS
1661=item DESTROY created new reference to dead object '%s'
1662
1663(F) A DESTROY() method created a new reference to the object which is
6903afa2
FC
1664just being DESTROYed. Perl is confused, and prefers to abort rather
1665than to create a dangling reference.
500ab966 1666
3cdd684c
TP
1667=item Did not produce a valid header
1668
1669See Server error.
1670
6df41af2
GS
1671=item %s did not return a true value
1672
1673(F) A required (or used) file must return a true value to indicate that
1674it compiled correctly and ran its initialization code correctly. It's
1675traditional to end such a file with a "1;", though any true value would
1676do. See L<perlfunc/require>.
1677
cc507455 1678=item (Did you mean &%s instead?)
4633a7c4 1679
413ff9f6
FC
1680(W misc) You probably referred to an imported subroutine &FOO as $FOO or
1681some such.
4633a7c4 1682
cc507455 1683=item (Did you mean "local" instead of "our"?)
33633739 1684
be771a83
GS
1685(W misc) Remember that "our" does not localize the declared global
1686variable. You have declared it again in the same lexical scope, which
1687seems superfluous.
33633739 1688
cc507455 1689=item (Did you mean $ or @ instead of %?)
a0d0e21e 1690
be771a83
GS
1691(W) You probably said %hash{$key} when you meant $hash{$key} or
1692@hash{@keys}. On the other hand, maybe you just meant %hash and got
1693carried away.
748a9306 1694
7e1af8bc 1695=item Died
5f05dabc 1696
1697(F) You passed die() an empty string (the equivalent of C<die "">) or
075b00aa 1698you called it with no args and C<$@> was empty.
5f05dabc 1699
3cdd684c
TP
1700=item Document contains no data
1701
1702See Server error.
1703
62658f4d
PM
1704=item %s does not define %s::VERSION--version check failed
1705
1706(F) You said something like "use Module 42" but the Module did not
943fc58e 1707define a C<$VERSION>.
62658f4d 1708
49704364
WL
1709=item '/' does not take a repeat count
1710
1711(F) You cannot put a repeat count of any kind right after the '/' code.
1712See L<perlfunc/pack>.
1713
95cb0d72
FC
1714=item Don't know how to get file name
1715
1716(P) C<PerlIO_getname>, a perl internal I/O function specific to VMS, was
1717somehow called on another platform. This should not happen.
1718
4021c788 1719=item Don't know how to handle magic of type \%o
a0d0e21e
LW
1720
1721(P) The internal handling of magical variables has been cursed.
1722
1723=item do_study: out of memory
1724
1725(P) This should have been caught by safemalloc() instead.
1726
6df41af2
GS
1727=item (Do you need to predeclare %s?)
1728
56da5a46
RGS
1729(S syntax) This is an educated guess made in conjunction with the message
1730"%s found where operator expected". It often means a subroutine or module
6df41af2
GS
1731name is being referenced that hasn't been declared yet. This may be
1732because of ordering problems in your file, or because of a missing
be771a83
GS
1733"sub", "package", "require", or "use" statement. If you're referencing
1734something that isn't defined yet, you don't actually have to define the
1735subroutine or package before the current location. You can use an empty
1736"sub foo;" or "package FOO;" to enter a "forward" declaration.
6df41af2 1737
ac206dc8
RGS
1738=item dump() better written as CORE::dump()
1739
1740(W misc) You used the obsolescent C<dump()> built-in function, without fully
1741qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
1742
84d78eb7
YO
1743=item dump is not supported
1744
1745(F) Your machine doesn't support dump/undump.
1746
a0d0e21e
LW
1747=item Duplicate free() ignored
1748
be771a83
GS
1749(S malloc) An internal routine called free() on something that had
1750already been freed.
a0d0e21e 1751
1109a392
MHM
1752=item Duplicate modifier '%c' after '%c' in %s
1753
35f0cd76
FC
1754(W unpack) You have applied the same modifier more than once after a
1755type in a pack template. See L<perlfunc/pack>.
1109a392 1756
0953b66b
FC
1757=item each on reference is experimental
1758
0773cb3e
FC
1759(S experimental::autoderef) C<each> with a scalar argument is experimental
1760and may change or be removed in a future Perl version. If you want to
1761take the risk of using this feature, simply disable this warning:
0953b66b 1762
d401967c 1763 no warnings "experimental::autoderef";
0953b66b 1764
4633a7c4
LW
1765=item elseif should be elsif
1766
fa816bf3
FC
1767(S syntax) There is no keyword "elseif" in Perl because Larry thinks
1768it's ugly. Your code will be interpreted as an attempt to call a method
1769named "elseif" for the class returned by the following block. This is
4633a7c4
LW
1770unlikely to be what you want.
1771
e0e4a6e3 1772=item Empty \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 1773
af6f566e 1774(F) C<\p> and C<\P> are used to introduce a named Unicode property, as
6903afa2 1775described in L<perlunicode> and L<perlre>. You used C<\p> or C<\P> in
af6f566e 1776a regular expression without specifying the property name.
ab13f0c7 1777
85ab1d1d 1778=item entering effective %s failed
5ff3f7a4 1779
85ab1d1d 1780(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
1781effective uids or gids failed.
1782
c038024b
RGS
1783=item %ENV is aliased to %s
1784
1785(F) You're running under taint mode, and the C<%ENV> variable has been
1786aliased to another hash, so it doesn't reflect anymore the state of the
6903afa2 1787program's environment. This is potentially insecure.
c038024b 1788
748a9306
LW
1789=item Error converting file specification %s
1790
5f05dabc 1791(F) An error peculiar to VMS. Because Perl may have to deal with file
748a9306 1792specifications in either VMS or Unix syntax, it converts them to a
be771a83
GS
1793single form when it must operate on them directly. Either you've passed
1794an invalid file specification to Perl, or you've found a case the
1795conversion routines don't handle. Drat.
748a9306 1796
ff56e4f1
KW
1797=item Escape literal pattern white space under /x
1798
1799(D deprecated) You compiled a regular expression pattern with C</x> to
1800ignore white space, and you used, as a literal, one of the characters
1801that Perl plans to eventually treat as white space. The character must
1802be escaped somehow, or it will work differently on a future Perl that
1803does treat it as white space. The easiest way is to insert a backslash
1804immediately before it, or to enclose it with square brackets. This
1805change is to bring Perl into conformance with Unicode recommendations.
1806Here are the five characters that generate this warning:
1807U+0085 NEXT LINE,
1808U+200E LEFT-TO-RIGHT MARK,
1809U+200F RIGHT-TO-LEFT MARK,
1810U+2028 LINE SEPARATOR,
1811and
1812U+2029 PARAGRAPH SEPARATOR.
1813
ad19ef22 1814=item Eval-group in insecure regular expression
e4d48cc9 1815
be771a83
GS
1816(F) Perl detected tainted data when trying to compile a regular
1817expression that contains the C<(?{ ... })> zero-width assertion, which
1818is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
e4d48cc9 1819
ad19ef22 1820=item Eval-group not allowed at runtime, use re 'eval' in regex m/%s/
e4d48cc9 1821
be771a83
GS
1822(F) Perl tried to compile a regular expression containing the
1823C<(?{ ... })> zero-width assertion at run time, as it would when the
f11307f5
FC
1824pattern contains interpolated values. Since that is a security risk,
1825it is not allowed. If you insist, you may still do this by using the
1826C<re 'eval'> pragma or by explicitly building the pattern from an
1827interpolated string at run time and using that in an eval(). See
1828L<perlre/(?{ code })>.
e4d48cc9 1829
ad19ef22 1830=item Eval-group not allowed, use re 'eval' in regex m/%s/
6df41af2 1831
be771a83
GS
1832(F) A regular expression contained the C<(?{ ... })> zero-width
1833assertion, but that construct is only allowed when the C<use re 'eval'>
1834pragma is in effect. See L<perlre/(?{ code })>.
6df41af2 1835
e0e4a6e3
FC
1836=item EVAL without pos change exceeded limit in regex; marked by
1837S<<-- HERE> in m/%s/
1a147d38
YO
1838
1839(F) You used a pattern that nested too many EVAL calls without consuming
6903afa2 1840any text. Restructure the pattern so that text is consumed.
1a147d38 1841
9e3ec65c 1842The <-- HERE shows whereabouts in the regular expression the problem was
1a147d38
YO
1843discovered.
1844
fc36a67e 1845=item Excessively long <> operator
1846
1847(F) The contents of a <> operator may not exceed the maximum size of a
1848Perl identifier. If you're just trying to glob a long list of
1849filenames, try using the glob() operator, or put the filenames into a
1850variable and glob that.
1851
ed9aa3b7
SG
1852=item exec? I'm not *that* kind of operating system
1853
af8bb25a 1854(F) The C<exec> function is not implemented on some systems, e.g., Symbian
6903afa2 1855OS. See L<perlport>.
ed9aa3b7 1856
fe13d51d 1857=item Execution of %s aborted due to compilation errors.
a0d0e21e
LW
1858
1859(F) The final summary message when a Perl compilation fails.
1860
0ffcbc25
FC
1861=item exists argument is not a HASH or ARRAY element or a subroutine
1862
4a0af295 1863(F) The argument to C<exists> must be a hash or array element or a
0ffcbc25
FC
1864subroutine with an ampersand, such as:
1865
1866 $foo{$bar}
1867 $ref->{"susie"}[12]
1868 &do_something
1869
1870=item exists argument is not a subroutine name
1871
ccfc2567
FC
1872(F) The argument to C<exists> for C<exists &sub> must be a subroutine name,
1873and not a subroutine call. C<exists &sub()> will generate this error.
0ffcbc25 1874
a0d0e21e
LW
1875=item Exiting eval via %s
1876
be771a83
GS
1877(W exiting) You are exiting an eval by unconventional means, such as a
1878goto, or a loop control statement.
e476b1b5
GS
1879
1880=item Exiting format via %s
1881
9a2ff54b 1882(W exiting) You are exiting a format by unconventional means, such as a
be771a83 1883goto, or a loop control statement.
a0d0e21e 1884
0a753a76 1885=item Exiting pseudo-block via %s
1886
be771a83
GS
1887(W exiting) You are exiting a rather special block construct (like a
1888sort block or subroutine) by unconventional means, such as a goto, or a
1889loop control statement. See L<perlfunc/sort>.
0a753a76 1890
a0d0e21e
LW
1891=item Exiting subroutine via %s
1892
be771a83
GS
1893(W exiting) You are exiting a subroutine by unconventional means, such
1894as a goto, or a loop control statement.
a0d0e21e
LW
1895
1896=item Exiting substitution via %s
1897
be771a83
GS
1898(W exiting) You are exiting a substitution by unconventional means, such
1899as a return, a goto, or a loop control statement.
a0d0e21e 1900
e0e4a6e3 1901=item Expecting close bracket in regex; marked by S<<-- HERE> in m/%s/
c608e803 1902
675fa9ff 1903(F) You wrote something like
c608e803
KW
1904
1905 (?13
1906
1907to denote a capturing group of the form
1908L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>,
1909but omitted the C<")">.
1910
e0e4a6e3 1911=item Expecting '(?flags:(?[...' in regex; marked by S<<-- HERE> in m/%s/
27350048 1912
8b6fbf55
FC
1913(F) The C<(?[...])> extended character class regular expression construct
1914only allows character classes (including character class escapes like
1915C<\d>), operators, and parentheses. The one exception is C<(?flags:...)>
1916containing at least one flag and exactly one C<(?[...])> construct.
27350048
FC
1917This allows a regular expression containing just C<(?[...])> to be
1918interpolated. If you see this error message, then you probably
1919have some other C<(?...)> construct inside your character class. See
1920L<perlrecharclass/Extended Bracketed Character Classes>.
1921
30d9c59b
Z
1922=item Experimental subroutine signatures not enabled
1923
1924(F) To use subroutine signatures, you must first enable them:
1925
caa35032 1926 no warnings "experimental::signatures";
30d9c59b
Z
1927 use feature "signatures";
1928 sub foo ($left, $right) { ... }
1929
6da34ecb
FC
1930=item Experimental "%s" subs not enabled
1931
1932(F) To use lexical subs, you must first enable them:
1933
1934 no warnings 'experimental::lexical_subs';
1935 use feature 'lexical_subs';
1936 my sub foo { ... }
1937
7b8d334a
GS
1938=item Explicit blessing to '' (assuming package main)
1939
be771a83
GS
1940(W misc) You are blessing a reference to a zero length string. This has
1941the effect of blessing the reference into the package main. This is
1942usually not what you want. Consider providing a default target package,
1943e.g. bless($ref, $p || 'MyPackage');
7b8d334a 1944
6df41af2
GS
1945=item %s: Expression syntax
1946
be771a83
GS
1947(A) You've accidentally run your script through B<csh> instead of Perl.
1948Check the #! line, or manually feed your script into Perl yourself.
6df41af2
GS
1949
1950=item %s failed--call queue aborted
1951
3c10abe3
AG
1952(F) An untrapped exception was raised while executing a UNITCHECK,
1953CHECK, INIT, or END subroutine. Processing of the remainder of the
1954queue of such routines has been prematurely ended.
6df41af2 1955
e0e4a6e3 1956=item False [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
73b437c8 1957
98d31c73 1958(W regexp)(F) A character class range must start and end at a literal
7253e4e3 1959character, not another character class like C<\d> or C<[:alpha:]>. The "-"
3c6ca74a
FC
1960in your false range is interpreted as a literal "-". In a C<(?[...])>
1961construct, this is an error, rather than a warning. Consider quoting
e0e4a6e3 1962the "-", "\-". The S<<-- HERE> shows whereabouts in the regular expression
3c6ca74a 1963the problem was discovered. See L<perlre>.
73b437c8 1964
1b1ee2ef 1965=item Fatal VMS error (status=%d) at %s, line %d
a0d0e21e 1966
be771a83
GS
1967(P) An error peculiar to VMS. Something untoward happened in a VMS
1968system service or RTL routine; Perl's exit status should provide more
1969details. The filename in "at %s" and the line number in "line %d" tell
1970you which section of the Perl source code is distressed.
a0d0e21e
LW
1971
1972=item fcntl is not implemented
1973
1974(F) Your machine apparently doesn't implement fcntl(). What is this, a
1975PDP-11 or something?
1976
22846ab4
AB
1977=item FETCHSIZE returned a negative value
1978
1979(F) A tied array claimed to have a negative number of elements, which
1980is not possible.
1981
f337b084
TH
1982=item Field too wide in 'u' format in pack
1983
d8b5cc61 1984(W pack) Each line in an uuencoded string starts with a length indicator
6903afa2
FC
1985which can't encode values above 63. So there is no point in asking for
1986a line length bigger than that. Perl will behave as if you specified
5c96f6f7 1987C<u63> as the format.
f337b084 1988
af8c498a 1989=item Filehandle %s opened only for input
a0d0e21e 1990
6c8d78fb
HS
1991(W io) You tried to write on a read-only filehandle. If you intended
1992it to be a read-write filehandle, you needed to open it with "+<" or
1993"+>" or "+>>" instead of with "<" or nothing. If you intended only to
1994write the file, use ">" or ">>". See L<perlfunc/open>.
a0d0e21e 1995
af8c498a 1996=item Filehandle %s opened only for output
a0d0e21e 1997
6c8d78fb
HS
1998(W io) You tried to read from a filehandle opened only for writing, If
1999you intended it to be a read/write filehandle, you needed to open it
89a1bda8
FC
2000with "+<" or "+>" or "+>>" instead of with ">". If you intended only to
2001read from the file, use "<". See L<perlfunc/open>. Another possibility
2002is that you attempted to open filedescriptor 0 (also known as STDIN) for
2003output (maybe you closed STDIN earlier?).
97828cef
RGS
2004
2005=item Filehandle %s reopened as %s only for input
2006
2007(W io) You opened for reading a filehandle that got the same filehandle id
6903afa2 2008as STDOUT or STDERR. This occurred because you closed STDOUT or STDERR
97828cef
RGS
2009previously.
2010
2011=item Filehandle STDIN reopened as %s only for output
2012
2013(W io) You opened for writing a filehandle that got the same filehandle id
fa816bf3 2014as STDIN. This occurred because you closed STDIN previously.
a0d0e21e
LW
2015
2016=item Final $ should be \$ or $name
2017
2018(F) You must now decide whether the final $ in a string was meant to be
be771a83
GS
2019a literal dollar sign, or was meant to introduce a variable name that
2020happens to be missing. So you have to put either the backslash or the
2021name.
a0d0e21e 2022
56e90b21
GS
2023=item flock() on closed filehandle %s
2024
be771a83 2025(W closed) The filehandle you're attempting to flock() got itself closed
c289d2f7 2026some time before now. Check your control flow. flock() operates on
be771a83
GS
2027filehandles. Are you attempting to call flock() on a dirhandle by the
2028same name?
56e90b21 2029
6df41af2
GS
2030=item Format not terminated
2031
2032(F) A format must be terminated by a line with a solitary dot. Perl got
2033to the end of your file without finding such a line.
2034
a0d0e21e
LW
2035=item Format %s redefined
2036
e476b1b5 2037(W redefine) You redefined a format. To suppress this warning, say
a0d0e21e
LW
2038
2039 {
271595cc 2040 no warnings 'redefine';
a0d0e21e
LW
2041 eval "format NAME =...";
2042 }
2043
a0d0e21e
LW
2044=item Found = in conditional, should be ==
2045
e476b1b5 2046(W syntax) You said
a0d0e21e
LW
2047
2048 if ($foo = 123)
2049
2050when you meant
2051
2052 if ($foo == 123)
2053
2054(or something like that).
2055
6df41af2
GS
2056=item %s found where operator expected
2057
56da5a46
RGS
2058(S syntax) The Perl lexer knows whether to expect a term or an operator.
2059If it sees what it knows to be a term when it was expecting to see an
be771a83
GS
2060operator, it gives you this warning. Usually it indicates that an
2061operator or delimiter was omitted, such as a semicolon.
6df41af2 2062
a0d0e21e
LW
2063=item gdbm store returned %d, errno %d, key "%s"
2064
2065(S) A warning from the GDBM_File extension that a store failed.
2066
2067=item gethostent not implemented
2068
2069(F) Your C library apparently doesn't implement gethostent(), probably
2070because if it did, it'd feel morally obligated to return every hostname
2071on the Internet.
2072
69282e91 2073=item get%sname() on closed socket %s
a0d0e21e 2074
be771a83
GS
2075(W closed) You tried to get a socket or peer socket name on a closed
2076socket. Did you forget to check the return value of your socket() call?
a0d0e21e 2077
748a9306
LW
2078=item getpwnam returned invalid UIC %#o for user "%s"
2079
2080(S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
2081C<getpwnam> operator returned an invalid UIC.
2082
6df41af2
GS
2083=item getsockopt() on closed socket %s
2084
be771a83
GS
2085(W closed) You tried to get a socket option on a closed socket. Did you
2086forget to check the return value of your socket() call? See
6df41af2
GS
2087L<perlfunc/getsockopt>.
2088
0f539b13
BF
2089=item given is experimental
2090
675fa9ff
FC
2091(S experimental::smartmatch) C<given> depends on smartmatch, which
2092is experimental, so its behavior may change or even be removed
2093in any future release of perl. See the explanation under
2094L<perlsyn/Experimental Details on given and when>.
0f539b13 2095
6df41af2
GS
2096=item Global symbol "%s" requires explicit package name
2097
a4edf47d 2098(F) You've said "use strict" or "use strict vars", which indicates
30c282f6 2099that all variables must either be lexically scoped (using "my" or "state"),
a4edf47d
GS
2100declared beforehand using "our", or explicitly qualified to say
2101which package the global variable is in (using "::").
6df41af2 2102
e476b1b5
GS
2103=item glob failed (%s)
2104
5ead438e 2105(S glob) Something went wrong with the external program(s) used
73c4e9dc
FC
2106for C<glob> and C<< <*.c> >>. Usually, this means that you supplied a C<glob>
2107pattern that caused the external program to fail and exit with a
be771a83 2108nonzero status. If the message indicates that the abnormal exit
73c4e9dc
FC
2109resulted in a coredump, this may also mean that your csh (C shell)
2110is broken. If so, you should change all of the csh-related variables
2111in config.sh: If you have tcsh, make the variables refer to it as
2112if it were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them
2113all empty (except that C<d_csh> should be C<'undef'>) so that Perl will
be771a83 2114think csh is missing. In either case, after editing config.sh, run
75b44862 2115C<./Configure -S> and rebuild Perl.
e476b1b5 2116
a0d0e21e
LW
2117=item Glob not terminated
2118
2119(F) The lexer saw a left angle bracket in a place where it was expecting
be771a83
GS
2120a term, so it's looking for the corresponding right angle bracket, and
2121not finding it. Chances are you left some needed parentheses out
2122earlier in the line, and you really meant a "less than".
a0d0e21e 2123
bcd05b94 2124=item gmtime(%f) too large
8b56d6ff 2125
e9200be3 2126(W overflow) You called C<gmtime> with a number that was larger than
fc003d4b 2127it can reliably handle and C<gmtime> probably returned the wrong
6903afa2 2128date. This warning is also triggered with NaN (the special
fc003d4b
MS
2129not-a-number value).
2130
bcd05b94 2131=item gmtime(%f) too small
fc003d4b 2132
e9200be3 2133(W overflow) You called C<gmtime> with a number that was smaller than
e7a1a147 2134it can reliably handle and C<gmtime> probably returned the wrong date.
8b56d6ff 2135
6df41af2 2136=item Got an error from DosAllocMem
a0d0e21e 2137
6df41af2
GS
2138(P) An error peculiar to OS/2. Most probably you're using an obsolete
2139version of Perl, and this should not happen anyway.
a0d0e21e
LW
2140
2141=item goto must have label
2142
2143(F) Unlike with "next" or "last", you're not allowed to goto an
2144unspecified destination. See L<perlfunc/goto>.
2145
6651ba0b
FC
2146=item Goto undefined subroutine%s
2147
2148(F) You tried to call a subroutine with C<goto &sub> syntax, but
2149the indicated subroutine hasn't been defined, or if it was, it
2150has since been undefined.
2151
6fbc9859 2152=item Group name must start with a non-digit word character in regex; marked by
e0e4a6e3 2153S<<-- HERE> in m/%s/
1f4f6bf1
YO
2154
2155(F) Group names must follow the rules for perl identifiers, meaning
f26c79ba
FC
2156they must start with a non-digit word character. A common cause of
2157this error is using (?&0) instead of (?0). See L<perlre>.
1f4f6bf1 2158
5a25739d
FC
2159=item ()-group starts with a count
2160
2161(F) A ()-group started with a count. A count is supposed to follow
2162something: a template character or a ()-group. See L<perlfunc/pack>.
2163
fe13d51d 2164=item %s had compilation errors.
6df41af2
GS
2165
2166(F) The final summary message when a C<perl -c> fails.
2167
a0d0e21e
LW
2168=item Had to create %s unexpectedly
2169
be771a83
GS
2170(S internal) A routine asked for a symbol from a symbol table that ought
2171to have existed already, but for some reason it didn't, and had to be
2172created on an emergency basis to prevent a core dump.
a0d0e21e
LW
2173
2174=item Hash %%s missing the % in argument %d of %s()
2175
be771a83
GS
2176(D deprecated) Really old Perl let you omit the % on hash names in some
2177spots. This is now heavily deprecated.
a0d0e21e 2178
6df41af2
GS
2179=item %s has too many errors
2180
2181(F) The parser has given up trying to parse the program after 10 errors.
2182Further error messages would likely be uninformative.
2183
252aa082
JH
2184=item Hexadecimal number > 0xffffffff non-portable
2185
e476b1b5 2186(W portable) The hexadecimal number you specified is larger than 2**32-1
9e24b6e2
JH
2187(4294967295) and therefore non-portable between systems. See
2188L<perlport> for more on portability concerns.
252aa082 2189
8903cb82 2190=item Identifier too long
2191
2192(F) Perl limits identifiers (names for variables, functions, etc.) to
fc36a67e 2193about 250 characters for simple names, and somewhat more for compound
be771a83
GS
2194names (like C<$A::B>). You've exceeded Perl's limits. Future versions
2195of Perl are likely to eliminate these arbitrary limitations.
8903cb82 2196
e0e4a6e3
FC
2197=item Ignoring zero length \N{} in character class in regex; marked by
2198S<<-- HERE> in m/%s/
fc8cd66c 2199
b5e3739b
FC
2200(W regexp) Named Unicode character escapes C<(\N{...})> may return a
2201zero-length sequence. When such an escape is used in a character class
2202its behaviour is not well defined. Check that the correct escape has
fc8cd66c
YO
2203been used, and the correct charname handler is in scope.
2204
6df41af2 2205=item Illegal binary digit %s
f675dbe5 2206
6df41af2 2207(F) You used a digit other than 0 or 1 in a binary number.
f675dbe5 2208
6df41af2 2209=item Illegal binary digit %s ignored
a0d0e21e 2210
be771a83
GS
2211(W digit) You may have tried to use a digit other than 0 or 1 in a
2212binary number. Interpretation of the binary number stopped before the
2213offending digit.
a0d0e21e 2214
6597eb22
FC
2215=item Illegal character after '_' in prototype for %s : %s
2216
e4d150f1
FC
2217(W illegalproto) An illegal character was found in a prototype
2218declaration. The '_' in a prototype must be followed by a ';',
2219indicating the rest of the parameters are optional, or one of '@'
2220or '%', since those two will accept 0 or more final parameters.
6597eb22 2221
78d0fecf 2222=item Illegal character \%o (carriage return)
4fdae800 2223
d5898338 2224(F) Perl normally treats carriage returns in the program text as it
be771a83
GS
2225would any other whitespace, which means you should never see this error
2226when Perl was built using standard options. For some reason, your
2227version of Perl appears to have been built without this support. Talk
2228to your Perl administrator.
4fdae800 2229
d37a9538
ST
2230=item Illegal character in prototype for %s : %s
2231
197afce1 2232(W illegalproto) An illegal character was found in a prototype declaration.
2e9cc7ef 2233Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
30d9c59b
Z
2234Perhaps you were trying to write a subroutine signature but didn't enable
2235that feature first (C<use feature 'signatures'>), so your signature was
2236instead interpreted as a bad prototype.
d37a9538 2237
904d85c5
RGS
2238=item Illegal declaration of anonymous subroutine
2239
2240(F) When using the C<sub> keyword to construct an anonymous subroutine,
6903afa2 2241you must always specify a block of code. See L<perlsub>.
904d85c5 2242
8e742a20
MHM
2243=item Illegal declaration of subroutine %s
2244
6903afa2 2245(F) A subroutine was not declared correctly. See L<perlsub>.
8e742a20 2246
a0d0e21e
LW
2247=item Illegal division by zero
2248
be771a83
GS
2249(F) You tried to divide a number by 0. Either something was wrong in
2250your logic, or you need to put a conditional in to guard against
2251meaningless input.
a0d0e21e 2252
6df41af2
GS
2253=item Illegal hexadecimal digit %s ignored
2254
be771a83
GS
2255(W digit) You may have tried to use a character other than 0 - 9 or
2256A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
2257number stopped before the illegal character.
6df41af2 2258
a0d0e21e
LW
2259=item Illegal modulus zero
2260
be771a83
GS
2261(F) You tried to divide a number by 0 to get the remainder. Most
2262numbers don't take to this kindly.
a0d0e21e 2263
6df41af2 2264=item Illegal number of bits in vec
399388f4 2265
6df41af2
GS
2266(F) The number of bits in vec() (the third argument) must be a power of
2267two from 1 to 32 (or 64, if your platform supports that).
399388f4
GS
2268
2269=item Illegal octal digit %s
a0d0e21e 2270
d1be9408 2271(F) You used an 8 or 9 in an octal number.
a0d0e21e 2272
399388f4 2273=item Illegal octal digit %s ignored
748a9306 2274
d1be9408 2275(W digit) You may have tried to use an 8 or 9 in an octal number.
75b44862 2276Interpretation of the octal number stopped before the 8 or 9.
748a9306 2277
e0e4a6e3 2278=item Illegal pattern in regex; marked by S<<-- HERE> in m/%s/
c608e803 2279
675fa9ff 2280(F) You wrote something like
c608e803
KW
2281
2282 (?+foo)
2283
2284The C<"+"> is valid only when followed by digits, indicating a
2285capturing group. See
2286L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>.
2287
fe13d51d 2288=item Illegal switch in PERL5OPT: -%c
6ff81951 2289
6df41af2 2290(X) The PERL5OPT environment variable may only be used to set the
646ca9b2 2291following switches: B<-[CDIMUdmtw]>.
6ff81951 2292
6df41af2 2293=item Ill-formed CRTL environ value "%s"
81e118e0 2294
75b44862 2295(W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
be771a83
GS
2296internal environ array, and encountered an element without the C<=>
2297delimiter used to separate keys from values. The element is ignored.
09bef843 2298
6df41af2 2299=item Ill-formed message in prime_env_iter: |%s|
54310121 2300
be771a83
GS
2301(W internal) A warning peculiar to VMS. Perl tried to read a logical
2302name or CLI symbol definition when preparing to iterate over %ENV, and
2303didn't see the expected delimiter between key and value, so the line was
2304ignored.
54310121 2305
6df41af2 2306=item (in cleanup) %s
9607fc9c 2307
be771a83
GS
2308(W misc) This prefix usually indicates that a DESTROY() method raised
2309the indicated exception. Since destructors are usually called by the
2310system at arbitrary points during execution, and often a vast number of
2311times, the warning is issued only once for any number of failures that
2312would otherwise result in the same message being repeated.
6df41af2 2313
be771a83
GS
2314Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
2315also result in this warning. See L<perlcall/G_KEEPERR>.
9607fc9c 2316
e0e4a6e3
FC
2317=item Incomplete expression within '(?[ ])' in regex; marked by S<<-- HERE>
2318in m/%s/
0d0b4b3b 2319
675fa9ff 2320(F) There was a syntax error within the C<(?[ ])>. This can happen if the
0d0b4b3b
KW
2321expression inside the construct was completely empty, or if there are
2322too many or few operands for the number of operators. Perl is not smart
2323enough to give you a more precise indication as to what is wrong.
2324
6fbc9859
MH
2325=item Inconsistent hierarchy during C3 merge of class '%s': merging failed on
2326parent '%s'
2c7d6b9c
RGS
2327
2328(F) The method resolution order (MRO) of the given class is not
2329C3-consistent, and you have enabled the C3 MRO for this class. See the C3
2330documentation in L<mro> for more information.
2331
979699d9
JH
2332=item In EBCDIC the v-string components cannot exceed 2147483647
2333
2334(F) An error peculiar to EBCDIC. Internally, v-strings are stored as
2335Unicode code points, and encoded in EBCDIC as UTF-EBCDIC. The UTF-EBCDIC
2336encoding is limited to code points no larger than 2147483647 (0x7FFFFFFF).
2337
6a2ed79a 2338=item Infinite recursion in regex
1a147d38
YO
2339
2340(F) You used a pattern that references itself without consuming any input
6903afa2 2341text. You should check the pattern to ensure that recursive patterns
1a147d38
YO
2342either consume text or fail.
2343
6dbe9451
NC
2344=item Initialization of state variables in list context currently forbidden
2345
6903afa2
FC
2346(F) Currently the implementation of "state" only permits the
2347initialization of scalar variables in scalar context. Re-write
2348C<state ($a) = 42> as C<state $a = 42> to change from list to scalar
2349context. Constructions such as C<state (@a) = foo()> will be
2350supported in a future perl release.
6dbe9451 2351
2186f873
FC
2352=item %%s[%s] in scalar context better written as $%s[%s]
2353
2354(W syntax) In scalar context, you've used an array index/value slice
2355(indicated by %) to select a single element of an array. Generally
2356it's better to ask for a scalar value (indicated by $). The difference
2357is that C<$foo[&bar]> always behaves like a scalar, both in the value it
2358returns and when evaluating its argument, while C<%foo[&bar]> provides
2359a list context to its subscript, which can do weird things if you're
2360expecting only one subscript. When called in list context, it also
2361returns the index (what C<&bar> returns) in addition to the value.
2362
2363=item %%s{%s} in scalar context better written as $%s{%s}
2364
2365(W syntax) In scalar context, you've used a hash key/value slice
2366(indicated by %) to select a single element of a hash. Generally it's
2367better to ask for a scalar value (indicated by $). The difference
2368is that C<$foo{&bar}> always behaves like a scalar, both in the value
2369it returns and when evaluating its argument, while C<@foo{&bar}> and
2370provides a list context to its subscript, which can do weird things
2371if you're expecting only one subscript. When called in list context,
2372it also returns the key in addition to the value.
2373
a0d0e21e
LW
2374=item Insecure dependency in %s
2375
8b1a09fc 2376(F) You tried to do something that the tainting mechanism didn't like.
be771a83
GS
2377The tainting mechanism is turned on when you're running setuid or
2378setgid, or when you specify B<-T> to turn it on explicitly. The
2379tainting mechanism labels all data that's derived directly or indirectly
2380from the user, who is considered to be unworthy of your trust. If any
2381such data is used in a "dangerous" operation, you get this error. See
2382L<perlsec> for more information.
a0d0e21e
LW
2383
2384=item Insecure directory in %s
2385
be771a83
GS
2386(F) You can't use system(), exec(), or a piped open in a setuid or
2387setgid script if C<$ENV{PATH}> contains a directory that is writable by
df98f984
RGS
2388the world. Also, the PATH must not contain any relative directory.
2389See L<perlsec>.
a0d0e21e 2390
62f468fc 2391=item Insecure $ENV{%s} while running %s
a0d0e21e
LW
2392
2393(F) You can't use system(), exec(), or a piped open in a setuid or
62f468fc 2394setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
332d5f78
SR
2395C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
2396supplied (or potentially supplied) by the user. The script must set
2397the path to a known value, using trustworthy data. See L<perlsec>.
a0d0e21e 2398
0e9be77f
DM
2399=item Insecure user-defined property %s
2400
2401(F) Perl detected tainted data when trying to compile a regular
2402expression that contains a call to a user-defined character property
2403function, i.e. C<\p{IsFoo}> or C<\p{InFoo}>.
2404See L<perlunicode/User-Defined Character Properties> and L<perlsec>.
2405
e0e4a6e3
FC
2406=item In '(?...)', splitting the initial '(?' is deprecated in regex;
2407marked by S<<-- HERE> in m/%s/
675fa9ff
FC
2408
2409(D regexp, deprecated) The two-character sequence C<"(?"> in
2410this context in a regular expression pattern should be an
2411indivisible token, with nothing intervening between the C<"(">
2412and the C<"?">, but you separated them. Due to an accident of
2413implementation, this prohibition was not enforced, but we do
2414plan to forbid it in a future Perl version. This message
2415serves as giving you fair warning of this pending change.
2416
b9ef414d
FC
2417=item Integer overflow in format string for %s
2418
2419(F) The indexes and widths specified in the format string of C<printf()>
2420or C<sprintf()> are too large. The numbers must not overflow the size of
2421integers for your architecture.
2422
a7ae9550
GS
2423=item Integer overflow in %s number
2424
35928bc5 2425(S overflow) The hexadecimal, octal or binary number you have specified
be771a83
GS
2426either as a literal or as an argument to hex() or oct() is too big for
2427your architecture, and has been converted to a floating point number.
2428On a 32-bit architecture the largest hexadecimal, octal or binary number
9e24b6e2
JH
2429representable without overflow is 0xFFFFFFFF, 037777777777, or
24300b11111111111111111111111111111111 respectively. Note that Perl
2431transparently promotes all numbers to a floating point representation
2432internally--subject to loss of precision errors in subsequent
2433operations.
bbce6d69 2434
fc89ca81
FC
2435=item Integer overflow in srand
2436
2437(S overflow) The number you have passed to srand is too big to fit
2438in your architecture's integer representation. The number has been
2439replaced with the largest integer supported (0xFFFFFFFF on 32-bit
2440architectures). This means you may be getting less randomness than
2441you expect, because different random seeds above the maximum will
2442return the same sequence of random numbers.
2443
46314c13
JP
2444=item Integer overflow in version
2445
18da5252
FC
2446=item Integer overflow in version %d
2447
784d71ed
FC
2448(W overflow) Some portion of a version initialization is too large for
2449the size of integers for your architecture. This is not a warning
f084e84f 2450because there is no rational reason for a version to try and use an
784d71ed
FC
2451element larger than typically 2**32. This is usually caused by trying
2452to use some odd mathematical operation as a version, like 100/9.
46314c13 2453
e0e4a6e3 2454=item Internal disaster in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2455
2456(P) Something went badly wrong in the regular expression parser.
e0e4a6e3 2457The S<<-- HERE> shows whereabouts in the regular expression the problem was
b45f050a
JF
2458discovered.
2459
748a9306
LW
2460=item Internal inconsistency in tracking vforks
2461
be771a83
GS
2462(S) A warning peculiar to VMS. Perl keeps track of the number of times
2463you've called C<fork> and C<exec>, to determine whether the current call
2464to C<exec> should affect the current script or a subprocess (see
2465L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
2466Perl is making a guess and treating this C<exec> as a request to
2467terminate the Perl script and execute the specified command.
748a9306 2468
870978ae
FC
2469=item internal %<num>p might conflict with future printf extensions
2470
2471(S internal) Perl's internal routine that handles C<printf> and C<sprintf>
2472formatting follows a slightly different set of rules when called from
2473C or XS code. Specifically, formats consisting of digits followed
2474by "p" (e.g., "%7p") are reserved for future use. If you see this
2475message, then an XS module tried to call that routine with one such
2476reserved format.
2477
e0e4a6e3 2478=item Internal urp in regex; marked by S<<-- HERE> in m/%s/
b45f050a 2479
fa816bf3 2480(P) Something went badly awry in the regular expression parser. The
e0e4a6e3 2481S<<-- HERE> shows whereabouts in the regular expression the problem was
7253e4e3 2482discovered.
a0d0e21e 2483
6df41af2
GS
2484=item %s (...) interpreted as function
2485
75b44862 2486(W syntax) You've run afoul of the rule that says that any list operator
be771a83 2487followed by parentheses turns into a function, with all the list
64977eb6 2488operators arguments found inside the parentheses. See
13a2d996 2489L<perlop/Terms and List Operators (Leftward)>.
6df41af2 2490
09bef843
SB
2491=item Invalid %s attribute: %s
2492
a4a4c9e2 2493(F) The indicated attribute for a subroutine or variable was not recognized
09bef843
SB
2494by Perl or by a user-supplied handler. See L<attributes>.
2495
2496=item Invalid %s attributes: %s
2497
a4a4c9e2 2498(F) The indicated attributes for a subroutine or variable were not
be771a83 2499recognized by Perl or by a user-supplied handler. See L<attributes>.
09bef843 2500
e0e4a6e3
FC
2501=item Invalid character in charnames alias definition; marked by
2502S<<-- HERE> in '%s
225fb84f
KW
2503
2504(F) You tried to create a custom alias for a character name, with
2505the C<:alias> option to C<use charnames> and the specified character in
2506the indicated name isn't valid. See L<charnames/CUSTOM ALIASES>.
2507
c8028aa6
TC
2508=item Invalid \0 character in %s for %s: %s\0%s
2509
fa3234e3
FC
2510(W syscalls) Embedded \0 characters in pathnames or other system call
2511arguments produce a warning as of 5.20. The parts after the \0 were
2512formerly ignored by system calls.
c8028aa6 2513
e0e4a6e3 2514=item Invalid character in \N{...}; marked by S<<-- HERE> in \N{%s}
a690c7c4
FC
2515
2516(F) Only certain characters are valid for character names. The
2517indicated one isn't. See L<charnames/CUSTOM ALIASES>.
2518
c635e13b 2519=item Invalid conversion in %s: "%s"
2520
be771a83
GS
2521(W printf) Perl does not understand the given format conversion. See
2522L<perlfunc/sprintf>.
c635e13b 2523
e0e4a6e3
FC
2524=item Invalid escape in the specified encoding in regex; marked by
2525S<<-- HERE> in m/%s/
9e08bc66 2526
98d31c73 2527(W regexp)(F) The numeric escape (for example C<\xHH>) of value < 256
9e08bc66
TS
2528didn't correspond to a single character through the conversion
2529from the encoding specified by the encoding pragma.
98d31c73
FC
2530The escape was replaced with REPLACEMENT CHARACTER (U+FFFD)
2531instead, except within S<C<(?[ ])>>, where it is a fatal error.
e0e4a6e3 2532The S<<-- HERE> shows whereabouts in the regular expression the
9e08bc66
TS
2533escape was discovered.
2534
8149aa9f
FC
2535=item Invalid hexadecimal number in \N{U+...}
2536
e0e4a6e3
FC
2537=item Invalid hexadecimal number in \N{U+...} in regex; marked by
2538S<<-- HERE> in m/%s/
aec0ef10 2539
8149aa9f 2540(F) The character constant represented by C<...> is not a valid hexadecimal
74f8e9e3
FC
2541number. Either it is empty, or you tried to use a character other than
25420 - 9 or A - F, a - f in a hexadecimal number.
8149aa9f 2543
6651ba0b
FC
2544=item Invalid module name %s with -%c option: contains single ':'
2545
2546(F) The module argument to perl's B<-m> and B<-M> command-line options
2547cannot contain single colons in the module name, but only in the
2548arguments after "=". In other words, B<-MFoo::Bar=:baz> is ok, but
2549B<-MFoo:Bar=baz> is not.
2550
2c7d6b9c
RGS
2551=item Invalid mro name: '%s'
2552
162a3e34
FC
2553(F) You tried to C<mro::set_mro("classname", "foo")> or C<use mro 'foo'>,
2554where C<foo> is not a valid method resolution order (MRO). Currently,
2555the only valid ones supported are C<dfs> and C<c3>, unless you have loaded
2556a module that is a MRO plugin. See L<mro> and L<perlmroapi>.
2c7d6b9c 2557
40e4140b
FC
2558=item Invalid negative number (%s) in chr
2559
2560(W utf8) You passed a negative number to C<chr>. Negative numbers are
2561not valid characters numbers, so it return the Unicode replacement
2562character (U+FFFD).
2563
6651ba0b
FC
2564=item invalid option -D%c, use -D'' to see choices
2565
8ff21bfe
FC
2566(S debugging) Perl was called with invalid debugger flags. Call perl
2567with the B<-D> option with no flags to see the list of acceptable values.
982c4ecb 2568See also L<perlrun/-Dletters>.
6651ba0b 2569
e0e4a6e3 2570=item Invalid [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2571
2572(F) The range specified in a character class had a minimum character
7253e4e3
RK
2573greater than the maximum character. One possibility is that you forgot the
2574C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
e0e4a6e3 2575up to C<ff>. The S<<-- HERE> shows whereabouts in the regular expression the
7253e4e3 2576problem was discovered. See L<perlre>.
6df41af2 2577
d1573ac7 2578=item Invalid range "%s" in transliteration operator
c2e66d9e
GS
2579
2580(F) The range specified in the tr/// or y/// operator had a minimum
2581character greater than the maximum character. See L<perlop>.
2582
09bef843
SB
2583=item Invalid separator character %s in attribute list
2584
0120eecf 2585(F) Something other than a colon or whitespace was seen between the
be771a83
GS
2586elements of an attribute list. If the previous attribute had a
2587parenthesised parameter list, perhaps that list was terminated too soon.
2588See L<attributes>.
09bef843 2589
b4581f09
JH
2590=item Invalid separator character %s in PerlIO layer specification %s
2591
2bfc5f71
FC
2592(W layer) When pushing layers onto the Perl I/O system, something other
2593than a colon or whitespace was seen between the elements of a layer list.
b4581f09
JH
2594If the previous attribute had a parenthesised parameter list, perhaps that
2595list was terminated too soon.
2596
2c86d456
DG
2597=item Invalid strict version format (%s)
2598
fa816bf3 2599(F) A version number did not meet the "strict" criteria for versions.
2c86d456
DG
2600A "strict" version number is a positive decimal number (integer or
2601decimal-fraction) without exponentiation or else a dotted-decimal
2602v-string with a leading 'v' character and at least three components.
a6485a24 2603The parenthesized text indicates which criteria were not met.
2c86d456
DG
2604See the L<version> module for more details on allowed version formats.
2605
49704364 2606=item Invalid type '%s' in %s
96e4d5b1 2607
49704364
WL
2608(F) The given character is not a valid pack or unpack type.
2609See L<perlfunc/pack>.
6728c851 2610
49704364 2611(W) The given character is not a valid pack or unpack type but used to be
75b44862 2612silently ignored.
96e4d5b1 2613
2c86d456
DG
2614=item Invalid version format (%s)
2615
fa816bf3 2616(F) A version number did not meet the "lax" criteria for versions.
2c86d456
DG
2617A "lax" version number is a positive decimal number (integer or
2618decimal-fraction) without exponentiation or else a dotted-decimal
fa816bf3
FC
2619v-string. If the v-string has fewer than three components, it
2620must have a leading 'v' character. Otherwise, the leading 'v' is
2621optional. Both decimal and dotted-decimal versions may have a
2622trailing "alpha" component separated by an underscore character
2623after a fractional or dotted-decimal component. The parenthesized
2624text indicates which criteria were not met. See the L<version> module
2625for more details on allowed version formats.
46314c13 2626
798ae1b7
DG
2627=item Invalid version object
2628
fa816bf3
FC
2629(F) The internal structure of the version object was invalid.
2630Perhaps the internals were modified directly in some way or
2631an arbitrary reference was blessed into the "version" class.
798ae1b7 2632
e0e4a6e3
FC
2633=item In '(*VERB...)', splitting the initial '(*' is deprecated in regex;
2634marked by S<<-- HERE> in m/%s/
675fa9ff
FC
2635
2636(D regexp, deprecated) The two-character sequence C<"(*"> in
2637this context in a regular expression pattern should be an
2638indivisible token, with nothing intervening between the C<"(">
f26c79ba 2639and the C<"*">, but you separated them. Due to an accident of
675fa9ff
FC
2640implementation, this prohibition was not enforced, but we do
2641plan to forbid it in a future Perl version. This message
2642serves as giving you fair warning of this pending change.
2643
a0d0e21e
LW
2644=item ioctl is not implemented
2645
2646(F) Your machine apparently doesn't implement ioctl(), which is pretty
2647strange for a machine that supports C.
2648
c289d2f7
JH
2649=item ioctl() on unopened %s
2650
2651(W unopened) You tried ioctl() on a filehandle that was never opened.
34b6fd5e 2652Check your control flow and number of arguments.
c289d2f7 2653
fe13d51d 2654=item IO layers (like '%s') unavailable
363c40c4
SB
2655
2656(F) Your Perl has not been configured to have PerlIO, and therefore
34b6fd5e 2657you cannot use IO layers. To have PerlIO, Perl must be configured
363c40c4
SB
2658with 'useperlio'.
2659
80cbd5ad
JH
2660=item IO::Socket::atmark not implemented on this architecture
2661
2662(F) Your machine doesn't implement the sockatmark() functionality,
34b6fd5e 2663neither as a system call nor an ioctl call (SIOCATMARK).
80cbd5ad 2664
4f650b80 2665=item $* is no longer supported
b4581f09 2666
4f650b80 2667(D deprecated, syntax) The special variable C<$*>, deprecated in older
ea9d9ebc 2668perls, has been removed as of 5.10.0 and is no longer supported. In
4f650b80
NC
2669previous versions of perl the use of C<$*> enabled or disabled multi-line
2670matching within a string.
4fd19576
B
2671
2672Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
6903afa2
FC
2673modifiers. You can enable C</m> for a lexical scope (even a whole file)
2674with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
570dedd4 2675then all regular expressions behaved as if they were written using C</m>.)
b4581f09 2676
8ae1fe26
RGS
2677=item $# is no longer supported
2678
a58ac25e 2679(D deprecated, syntax) The special variable C<$#>, deprecated in older
ea9d9ebc 2680perls, has been removed as of 5.10.0 and is no longer supported. You
a58ac25e 2681should use the printf/sprintf functions instead.
8ae1fe26 2682
ccf3535a 2683=item '%s' is not a code reference
6ad11d81 2684
6903afa2
FC
2685(W overload) The second (fourth, sixth, ...) argument of
2686overload::constant needs to be a code reference. Either
2687an anonymous subroutine, or a reference to a subroutine.
6ad11d81 2688
ccf3535a 2689=item '%s' is not an overloadable type
6ad11d81 2690
04a80ee0
RGS
2691(W overload) You tried to overload a constant type the overload package is
2692unaware of.
6ad11d81 2693
5a25739d
FC
2694=item -i used with no filenames on the command line, reading from STDIN
2695
2696(S inplace) The C<-i> option was passed on the command line, indicating
2697that the script is intended to edit files in place, but no files were
2698given. This is usually a mistake, since editing STDIN in place doesn't
2699make sense, and can be confusing because it can make perl look like
2700it is hanging when it is really just trying to read from STDIN. You
2701should either pass a filename to edit, or remove C<-i> from the command
2702line. See L<perlrun> for more details.
2703
aec0ef10 2704=item Junk on end of regexp in regex m/%s/
a0d0e21e
LW
2705
2706(P) The regular expression parser is confused.
2707
0953b66b
FC
2708=item keys on reference is experimental
2709
0773cb3e
FC
2710(S experimental::autoderef) C<keys> with a scalar argument is experimental
2711and may change or be removed in a future Perl version. If you want to
2712take the risk of using this feature, simply disable this warning:
0953b66b 2713
d401967c 2714 no warnings "experimental::autoderef";
0953b66b 2715
a0d0e21e
LW
2716=item Label not found for "last %s"
2717
be771a83
GS
2718(F) You named a loop to break out of, but you're not currently in a loop
2719of that name, not even if you count where you were called from. See
2720L<perlfunc/last>.
a0d0e21e
LW
2721
2722=item Label not found for "next %s"
2723
2724(F) You named a loop to continue, but you're not currently in a loop of
2725that name, not even if you count where you were called from. See
2726L<perlfunc/last>.
2727
2728=item Label not found for "redo %s"
2729
2730(F) You named a loop to restart, but you're not currently in a loop of
2731that name, not even if you count where you were called from. See
2732L<perlfunc/last>.
2733
85ab1d1d 2734=item leaving effective %s failed
5ff3f7a4 2735
85ab1d1d 2736(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
2737effective uids or gids failed.
2738
49704364
WL
2739=item length/code after end of string in unpack
2740
d7f8936a 2741(F) While unpacking, the string buffer was already used up when an unpack
6903afa2
FC
2742length/code combination tried to obtain more data. This results in
2743an undefined value for the length. See L<perlfunc/pack>.
49704364 2744
25e26107 2745=item length() used on %s (did you mean "scalar(%s)"?)
e508c8a4 2746
0d46a4e7
FC
2747(W syntax) You used length() on either an array or a hash when you
2748probably wanted a count of the items.
e508c8a4
MH
2749
2750Array size can be obtained by doing:
2751
2752 scalar(@array);
2753
2754The number of items in a hash can be obtained by doing:
2755
2756 scalar(keys %hash);
2757
f0e67a1d
Z
2758=item Lexing code attempted to stuff non-Latin-1 character into Latin-1 input
2759
d4fe7078
RS
2760(F) An extension is attempting to insert text into the current parse
2761(using L<lex_stuff_pvn|perlapi/lex_stuff_pvn> or similar), but tried to insert a character that
2762couldn't be part of the current input. This is an inherent pitfall
2763of the stuffing mechanism, and one of the reasons to avoid it. Where
6903afa2 2764it is necessary to stuff, stuffing only plain ASCII is recommended.
f0e67a1d
Z
2765
2766=item Lexing code internal error (%s)
2767
2768(F) Lexing code supplied by an extension violated the lexer's API in a
2769detectable way.
2770
69282e91 2771=item listen() on closed socket %s
a0d0e21e 2772
be771a83
GS
2773(W closed) You tried to do a listen on a closed socket. Did you forget
2774to check the return value of your socket() call? See
2775L<perlfunc/listen>.
a0d0e21e 2776
6651ba0b
FC
2777=item List form of piped open not implemented
2778
2779(F) On some platforms, notably Windows, the three-or-more-arguments
2780form of C<open> does not support pipes, such as C<open($pipe, '|-', @args)>.
2781Use the two-argument C<open($pipe, '|prog arg1 arg2...')> form instead.
2782
bcd05b94 2783=item localtime(%f) too large
8b56d6ff 2784
e9200be3 2785(W overflow) You called C<localtime> with a number that was larger
fc003d4b 2786than it can reliably handle and C<localtime> probably returned the
6903afa2 2787wrong date. This warning is also triggered with NaN (the special
fc003d4b
MS
2788not-a-number value).
2789
bcd05b94 2790=item localtime(%f) too small
fc003d4b 2791
e9200be3 2792(W overflow) You called C<localtime> with a number that was smaller
fc003d4b 2793than it can reliably handle and C<localtime> probably returned the
e7a1a147 2794wrong date.
8b56d6ff 2795
58e23c8d 2796=item Lookbehind longer than %d not implemented in regex m/%s/
b45f050a
JF
2797
2798(F) There is currently a limit on the length of string which lookbehind can
6903afa2 2799handle. This restriction may be eased in a future release.
2e50fd82 2800
b88df990
NC
2801=item Lost precision when %s %f by 1
2802
e63e8a91
FC
2803(W imprecision) The value you attempted to increment or decrement by one
2804is too large for the underlying floating point representation to store
2805accurately, hence the target of C<++> or C<--> is unchanged. Perl issues this
2806warning because it has already switched from integers to floating point
2807when values are too large for integers, and now even floating point is
2808insufficient. You may wish to switch to using L<Math::BigInt> explicitly.
b88df990 2809
93fad930 2810=item lstat() on filehandle%s
2f7da168
RK
2811
2812(W io) You tried to do an lstat on a filehandle. What did you mean
2813by that? lstat() makes sense only on filenames. (Perl did a fstat()
2814instead on the filehandle.)
2815
345d70e3 2816=item lvalue attribute %s already-defined subroutine
bb3abb05 2817
345d70e3
FC
2818(W misc) Although L<attributes.pm|attributes> allows this, turning the lvalue
2819attribute on or off on a Perl subroutine that is already defined
2820does not always work properly. It may or may not do what you
2821want, depending on what code is inside the subroutine, with exact
2822details subject to change between Perl versions. Only do this
2823if you really know what you are doing.
bb3abb05 2824
885ef6f5
GG
2825=item lvalue attribute ignored after the subroutine has been defined
2826
345d70e3
FC
2827(W misc) Using the C<:lvalue> declarative syntax to make a Perl
2828subroutine an lvalue subroutine after it has been defined is
2829not permitted. To make the subroutine an lvalue subroutine,
2830add the lvalue attribute to the definition, or put the C<sub
2831foo :lvalue;> declaration before the definition.
2832
2833See also L<attributes.pm|attributes>.
885ef6f5 2834
6f1b3ab0
FC
2835=item Magical list constants are not supported
2836
2837(F) You assigned a magical array to a stash element, and then tried
2838to use the subroutine from the same slot. You are asking Perl to do
2839something it cannot do, details subject to change between Perl versions.
2840
2db62bbc 2841=item Malformed integer in [] in pack
49704364 2842
2db62bbc 2843(F) Between the brackets enclosing a numeric repeat count only digits
49704364
WL
2844are permitted. See L<perlfunc/pack>.
2845
2846=item Malformed integer in [] in unpack
2847
2db62bbc 2848(F) Between the brackets enclosing a numeric repeat count only digits
49704364
WL
2849are permitted. See L<perlfunc/pack>.
2850
6df41af2
GS
2851=item Malformed PERLLIB_PREFIX
2852
2853(F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
2854
2855 prefix1;prefix2
2856
2857or
6df41af2
GS
2858 prefix1 prefix2
2859
be771a83
GS
2860with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
2861a builtin library search path, prefix2 is substituted. The error may
2862appear if components are not found, or are too long. See
fecfaeb8 2863"PERLLIB_PREFIX" in L<perlos2>.
6df41af2 2864
2f758a16
ST
2865=item Malformed prototype for %s: %s
2866
d37a9538
ST
2867(F) You tried to use a function with a malformed prototype. The
2868syntax of function prototypes is given a brief compile-time check for
2869obvious errors like invalid characters. A more rigorous check is run
2870when the function is called.
30d9c59b
Z
2871Perhaps the function's author was trying to write a subroutine signature
2872but didn't enable that feature first (C<use feature 'signatures'>),
2873so the signature was instead interpreted as a bad prototype.
2f758a16 2874
ba210ebe
JH
2875=item Malformed UTF-8 character (%s)
2876
4d6f11e5 2877(S utf8)(F) Perl detected a string that didn't comply with UTF-8
2575c402 2878encoding rules, even though it had the UTF8 flag on.
ba210ebe 2879
2575c402
JW
2880One possible cause is that you set the UTF8 flag yourself for data that
2881you thought to be in UTF-8 but it wasn't (it was for example legacy
6903afa2 28828-bit data). To guard against this, you can use Encode::decode_utf8.
2575c402
JW
2883
2884If you use the C<:encoding(UTF-8)> PerlIO layer for input, invalid byte
2885sequences are handled gracefully, but if you use C<:utf8>, the flag is
2886set without validating the data, possibly resulting in this error
2887message.
2888
2889See also L<Encode/"Handling Malformed Data">.
901b21bf 2890
107160e2
KW
2891=item Malformed UTF-8 character immediately after '%s'
2892
2893(F) You said C<use utf8>, but the program file doesn't comply with UTF-8
2894encoding rules. The message prints out the properly encoded characters
2895just before the first bad one. If C<utf8> warnings are enabled, a
2896warning is generated that gives more details about the type of
2897malformation.
2898
bde9e88d 2899=item Malformed UTF-8 returned by \N{%s} immediately after '%s'
ff3f963a
KW
2900
2901(F) The charnames handler returned malformed UTF-8.
2902
4a5d3a93
FC
2903=item Malformed UTF-8 string in '%c' format in unpack
2904
2905(F) You tried to unpack something that didn't comply with UTF-8 encoding
2906rules and perl was unable to guess how to make more progress.
2907
f337b084
TH
2908=item Malformed UTF-8 string in pack
2909
2910(F) You tried to pack something that didn't comply with UTF-8 encoding
2911rules and perl was unable to guess how to make more progress.
2912
2913=item Malformed UTF-8 string in unpack
2914
2915(F) You tried to unpack something that didn't comply with UTF-8 encoding
2916rules and perl was unable to guess how to make more progress.
2917
4a5d3a93 2918=item Malformed UTF-16 surrogate
f337b084 2919
4a5d3a93
FC
2920(F) Perl thought it was reading UTF-16 encoded character data but while
2921doing it Perl met a malformed Unicode surrogate.
2922
30d9c59b
Z
2923=item Mandatory parameter follows optional parameter
2924
2925(F) In a subroutine signature, you wrote something like "$a = undef,
2926$b", making an earlier parameter optional and a later one mandatory.
2927Parameters are filled from left to right, so it's impossible for the
2928caller to omit an earlier one and pass a later one. If you want to act
2929as if the parameters are filled from right to left, declare the rightmost
2930optional and then shuffle the parameters around in the subroutine's body.
2931
2d88a86a
KW
2932=item Matched non-Unicode code point 0x%X against Unicode property; may
2933not be portable
2934
2935(S non_unicode) Perl allows strings to contain a superset of
2936Unicode code points; each code point may be as large as what is storable
2937in an unsigned integer on your system, but these may not be accepted by
2938other languages/systems. This message occurs when you matched a string
2939containing such a code point against a regular expression pattern, and
2940the code point was matched against a Unicode property, C<\p{...}> or
2941C<\P{...}>. Unicode properties are only defined on Unicode code points,
2942so the result of this match is undefined by Unicode, but Perl (starting
2943in v5.20) treats non-Unicode code points as if they were typical
2944unassigned Unicode ones, and matched this one accordingly. Whether a
2945given property matches these code points or not is specified in
2946L<perluniprops/Properties accessible through \p{} and \P{}>.
2947
2948This message is suppressed (unless it has been made fatal) if it is
2949immaterial to the results of the match if the code point is Unicode or
2950not. For example, the property C<\p{ASCII_Hex_Digit}> only can match
2951the 22 characters C<[0-9A-Fa-f]>, so obviously all other code points,
2952Unicode or not, won't match it. (And C<\P{ASCII_Hex_Digit}> will match
2953every code point except these 22.)
2954
2955Getting this message indicates that the outcome of the match arguably
2956should have been the opposite of what actually happened. If you think
2957that is the case, you may wish to make the C<non_unicode> warnings
2958category fatal; if you agree with Perl's decision, you may wish to turn
2959off this category.
2960
2961See L<perlunicode/Beyond Unicode code points> for more information.
2962
e0e4a6e3
FC
2963=item %s matches null string many times in regex; marked by S<<-- HERE> in
2964m/%s/
4a5d3a93
FC
2965
2966(W regexp) The pattern you've specified would be an infinite loop if the
e0e4a6e3 2967regular expression engine didn't specifically check for that. The S<<-- HERE>
9e3ec65c 2968shows whereabouts in the regular expression the problem was discovered.
4a5d3a93 2969See L<perlre>.
f337b084 2970
de42a5a9 2971=item Maximal count of pending signals (%u) exceeded
2563cec5 2972
6903afa2 2973(F) Perl aborted due to too high a number of signals pending. This
2563cec5
IZ
2974usually indicates that your operating system tried to deliver signals
2975too fast (with a very high priority), starving the perl process from
2976resources it would need to reach a point where it can process signals
6903afa2 2977safely. (See L<perlipc/"Deferred Signals (Safe Signals)">.)
2563cec5 2978
25f58aea
PN
2979=item "%s" may clash with future reserved word
2980
2981(W) This warning may be due to running a perl5 script through a perl4
2982interpreter, especially if the word that is being warned about is
2983"use" or "my".
2984
0d2487cd 2985=item '%' may not be used in pack
6df41af2
GS
2986
2987(F) You can't pack a string by supplying a checksum, because the
be771a83
GS
2988checksumming process loses information, and you can't go the other way.
2989See L<perlfunc/unpack>.
6df41af2 2990
a0d0e21e
LW
2991=item Method for operation %s not found in package %s during blessing
2992
2993(F) An attempt was made to specify an entry in an overloading table that
e7ea3e70 2994doesn't resolve to a valid subroutine. See L<overload>.
a0d0e21e 2995
3cdd684c
TP
2996=item Method %s not permitted
2997
2998See Server error.
2999
a0d0e21e
LW
3000=item Might be a runaway multi-line %s string starting on line %d
3001
3002(S) An advisory indicating that the previous error may have been caused
3003by a missing delimiter on a string or pattern, because it eventually
3004ended earlier on the current line.
3005
3006=item Misplaced _ in number
3007
d4ced10d
JH
3008(W syntax) An underscore (underbar) in a numeric constant did not
3009separate two digits.
a0d0e21e 3010
7baa4690
HS
3011=item Missing argument in %s
3012
3013(W uninitialized) A printf-type format required more arguments than were
3014supplied.
3015
9e81e6a1
RGS
3016=item Missing argument to -%c
3017
3018(F) The argument to the indicated command line switch must follow
3019immediately after the switch, without intervening spaces.
3020
ff3f963a 3021=item Missing braces on \N{}
423cee85 3022
e0e4a6e3 3023=item Missing braces on \N{} in regex; marked by S<<-- HERE> in m/%s/
aec0ef10 3024
4a2d328f 3025(F) Wrong syntax of character name literal C<\N{charname}> within
532cb70d
FC
3026double-quotish context. This can also happen when there is a space
3027(or comment) between the C<\N> and the C<{> in a regex with the C</x> modifier.
3028This modifier does not change the requirement that the brace immediately
3029follow the C<\N>.
423cee85 3030
f0a2b745
KW
3031=item Missing braces on \o{}
3032
3033(F) A C<\o> must be followed immediately by a C<{> in double-quotish context.
3034
a0d0e21e
LW
3035=item Missing comma after first argument to %s function
3036
3037(F) While certain functions allow you to specify a filehandle or an
3038"indirect object" before the argument list, this ain't one of them.
3039
06eaf0bc
GS
3040=item Missing command in piped open
3041
be771a83
GS
3042(W pipe) You used the C<open(FH, "| command")> or
3043C<open(FH, "command |")> construction, but the command was missing or
3044blank.
06eaf0bc 3045
961ce445
RGS
3046=item Missing control char name in \c
3047
3048(F) A double-quoted string ended with "\c", without the required control
3049character name.
3050
591f5ca2
FC
3051=item Missing ']' in prototype for %s : %s
3052
bfe11873 3053(W illegalproto) A grouping was started with C<[> but never closed with C<]>.
591f5ca2 3054
8767b1ab 3055=item Missing name in "%s sub"
6df41af2 3056
87444db5 3057(F) The syntax for lexically scoped subroutines requires that
be771a83 3058they have a name with which they can be found.
6df41af2
GS
3059
3060=item Missing $ on loop variable
3061
be771a83
GS
3062(F) Apparently you've been programming in B<csh> too much. Variables
3063are always mentioned with the $ in Perl, unlike in the shells, where it
3064can vary from one line to the next.
6df41af2 3065
cc507455 3066=item (Missing operator before %s?)
748a9306 3067
56da5a46
RGS
3068(S syntax) This is an educated guess made in conjunction with the message
3069"%s found where operator expected". Often the missing operator is a comma.
748a9306 3070
e0e4a6e3 3071=item Missing right brace on \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 3072
ff3f963a
KW
3073(F) Missing right brace in C<\x{...}>, C<\p{...}>, C<\P{...}>, or C<\N{...}>.
3074
4a68bf9d 3075=item Missing right brace on \N{} or unescaped left brace after \N
ff3f963a 3076
d32207c9
FC
3077(F) C<\N> has two meanings.
3078
3079The traditional one has it followed by a name enclosed in braces,
3080meaning the character (or sequence of characters) given by that
fa816bf3 3081name. Thus C<\N{ASTERISK}> is another way of writing C<*>, valid in both
d32207c9
FC
3082double-quoted strings and regular expression patterns. In patterns,
3083it doesn't have the meaning an unescaped C<*> does.
3084
3085Starting in Perl 5.12.0, C<\N> also can have an additional meaning (only)
3086in patterns, namely to match a non-newline character. (This is short
3087for C<[^\n]>, and like C<.> but is not affected by the C</s> regex modifier.)
3088
3089This can lead to some ambiguities. When C<\N> is not followed immediately
3090by a left brace, Perl assumes the C<[^\n]> meaning. Also, if the braces
3091form a valid quantifier such as C<\N{3}> or C<\N{5,}>, Perl assumes that this
3092means to match the given quantity of non-newlines (in these examples,
30933; and 5 or more, respectively). In all other case, where there is a
3094C<\N{> and a matching C<}>, Perl assumes that a character name is desired.
3095
3096However, if there is no matching C<}>, Perl doesn't know if it was
3097mistakenly omitted, or if C<[^\n]{> was desired, and raises this error.
3098If you meant the former, add the right brace; if you meant the latter,
3099escape the brace with a backslash, like so: C<\N\{>
ab13f0c7 3100
d98d5fff 3101=item Missing right curly or square bracket
a0d0e21e 3102
be771a83
GS
3103(F) The lexer counted more opening curly or square brackets than closing
3104ones. As a general rule, you'll find it's missing near the place you
3105were last editing.
a0d0e21e 3106
6df41af2
GS
3107=item (Missing semicolon on previous line?)
3108
56da5a46
RGS
3109(S syntax) This is an educated guess made in conjunction with the message
3110"%s found where operator expected". Don't automatically put a semicolon on
6df41af2
GS
3111the previous line just because you saw this message.
3112
a0d0e21e
LW
3113=item Modification of a read-only value attempted
3114
3115(F) You tried, directly or indirectly, to change the value of a
5f05dabc 3116constant. You didn't, of course, try "2 = 1", because the compiler
a0d0e21e
LW
3117catches that. But an easy way to do the same thing is:
3118
3119 sub mod { $_[0] = 1 }
3120 mod(2);
3121
3122Another way is to assign to a substr() that's off the end of the string.
3123
c5674021
PDF
3124Yet another way is to assign to a C<foreach> loop I<VAR> when I<VAR>
3125is aliased to a constant in the look I<LIST>:
3126
b7e4ecc1
FC
3127 $x = 1;
3128 foreach my $n ($x, 2) {
3129 $n *= 2; # modifies the $x, but fails on attempt to
3130 } # modify the 2
c5674021 3131
7a4340ed 3132=item Modification of non-creatable array value attempted, %s
a0d0e21e
LW
3133
3134(F) You tried to make an array value spring into existence, and the
3135subscript was probably negative, even counting from end of the array
3136backwards.
3137
7a4340ed 3138=item Modification of non-creatable hash value attempted, %s
a0d0e21e 3139
be771a83
GS
3140(P) You tried to make a hash value spring into existence, and it
3141couldn't be created for some peculiar reason.
a0d0e21e
LW
3142
3143=item Module name must be constant
3144
3145(F) Only a bare module name is allowed as the first argument to a "use".
3146
be98fb35 3147=item Module name required with -%c option
6df41af2 3148
be98fb35
GS
3149(F) The C<-M> or C<-m> options say that Perl should load some module, but
3150you omitted the name of the module. Consult L<perlrun> for full details
3151about C<-M> and C<-m>.
6df41af2 3152
fe13d51d 3153=item More than one argument to '%s' open
ed9aa3b7 3154
6903afa2 3155(F) The C<open> function has been asked to open multiple files. This
ed9aa3b7
SG
3156can happen if you are trying to open a pipe to a command that takes a
3157list of arguments, but have forgotten to specify a piped open mode.
3158See L<perlfunc/open> for details.
3159
85396b18
FC
3160=item mprotect for COW string %p %u failed with %d
3161
3162(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3163L<perlguts/"Copy on Write">), but a shared string buffer
3164could not be made read-only.
3165
92951bce
FC
3166=item mprotect for %p %u failed with %d
3167
85396b18
FC
3168(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see L<perlhacktips>),
3169but an op tree could not be made read-only.
3170
3171=item mprotect RW for COW string %p %u failed with %d
3172
3173(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3174L<perlguts/"Copy on Write">), but a read-only shared string
3175buffer could not be made mutable.
3176
92951bce
FC
3177=item mprotect RW for %p %u failed with %d
3178
3179(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see
85396b18
FC
3180L<perlhacktips>), but a read-only op tree could not be made
3181mutable before freeing the ops.
92951bce 3182
a0d0e21e
LW
3183=item msg%s not implemented
3184
3185(F) You don't have System V message IPC on your system.
3186
3187=item Multidimensional syntax %s not supported
3188
75b44862
GS
3189(W syntax) Multidimensional arrays aren't written like C<$foo[1,2,3]>.
3190They're written like C<$foo[1][2][3]>, as in C.
8b1a09fc 3191
49704364 3192=item '/' must follow a numeric type in unpack
6df41af2 3193
49704364
WL
3194(F) You had an unpack template that contained a '/', but this did not
3195follow some unpack specification producing a numeric value.
3196See L<perlfunc/pack>.
6df41af2
GS
3197
3198=item "my sub" not yet implemented
3199
be771a83
GS
3200(F) Lexically scoped subroutines are not yet implemented. Don't try
3201that yet.
6df41af2 3202
5a25739d
FC
3203=item "my %s" used in sort comparison
3204
3205(W syntax) The package variables $a and $b are used for sort comparisons.
3206You used $a or $b in as an operand to the C<< <=> >> or C<cmp> operator inside a
3207sort comparison block, and the variable had earlier been declared as a
3208lexical variable. Either qualify the sort variable with the package
3209name, or rename the lexical variable.
3210
fd1b7234 3211=item "my" variable %s can't be in a package
6df41af2 3212
be771a83
GS
3213(F) Lexically scoped variables aren't in a package, so it doesn't make
3214sense to try to declare one with a package qualifier on the front. Use
3215local() if you want to localize a package variable.
09bef843 3216
8149aa9f
FC
3217=item Name "%s::%s" used only once: possible typo
3218
c59aba6c
FC
3219(W once) Typographical errors often show up as unique variable
3220names. If you had a good reason for having a unique name, then
3221just mention it again somehow to suppress the message. The C<our>
08a33b6b 3222declaration is also provided for this purpose.
c59aba6c 3223
08a33b6b
AP
3224NOTE: This warning detects package symbols that have been used only
3225once. This means lexical variables will never trigger this warning.
3226It also means that all of the package variables $c, @c, %c, as well
3227as *c, &c, sub c{}, c(), and c (the filehandle or
c59aba6c
FC
3228format) are considered the same; if a program uses $c only once
3229but also uses any of the others it will not trigger this warning.
3230Symbols beginning with an underscore and symbols using special
3231identifiers (q.v. L<perldata>) are exempt from this warning.
8149aa9f 3232
e0e4a6e3 3233=item Need exactly 3 octal digits in regex; marked by S<<-- HERE> in m/%s/
0d0b4b3b
KW
3234
3235(F) Within S<C<(?[ ])>>, all constants interpreted as octal need to be
3236exactly 3 digits long. This helps catch some ambiguities. If your
3237constant is too short, add leading zeros, like
3238
3239 (?[ [ \078 ] ]) # Syntax error!
3240 (?[ [ \0078 ] ]) # Works
3241 (?[ [ \007 8 ] ]) # Clearer
3242
3243The maximum number this construct can express is C<\777>. If you
675fa9ff
FC
3244need a larger one, you need to use L<\o{}|perlrebackslash/Octal escapes> instead. If you meant
3245two separate things, you need to separate them:
0d0b4b3b
KW
3246
3247 (?[ [ \7776 ] ]) # Syntax error!
3248 (?[ [ \o{7776} ] ]) # One meaning
3249 (?[ [ \777 6 ] ]) # Another meaning
3250 (?[ [ \777 \006 ] ]) # Still another
3251
49704364
WL
3252=item Negative '/' count in unpack
3253
3254(F) The length count obtained from a length/code unpack operation was
3255negative. See L<perlfunc/pack>.
3256
a0d0e21e
LW
3257=item Negative length
3258
be771a83
GS
3259(F) You tried to do a read/write/send/recv operation with a buffer
3260length that is less than 0. This is difficult to imagine.
a0d0e21e 3261
ed9aa3b7
SG
3262=item Negative offset to vec in lvalue context
3263
3264(F) When C<vec> is called in an lvalue context, the second argument must be
3265greater than or equal to zero.
3266
e0e4a6e3 3267=item Nested quantifiers in regex; marked by S<<-- HERE> in m/%s/
a0d0e21e 3268
6903afa2 3269(F) You can't quantify a quantifier without intervening parentheses.
e0e4a6e3 3270So things like ** or +* or ?* are illegal. The S<<-- HERE> shows
9e3ec65c 3271whereabouts in the regular expression the problem was discovered.
a0d0e21e 3272
7253e4e3 3273Note that the minimal matching quantifiers, C<*?>, C<+?>, and
be771a83 3274C<??> appear to be nested quantifiers, but aren't. See L<perlre>.
a0d0e21e 3275
6df41af2 3276=item %s never introduced
a0d0e21e 3277
be771a83
GS
3278(S internal) The symbol in question was declared but somehow went out of
3279scope before it could possibly have been used.
a0d0e21e 3280
2c7d6b9c
RGS
3281=item next::method/next::can/maybe::next::method cannot find enclosing method
3282
3283(F) C<next::method> needs to be called within the context of a
3284real method in a real package, and it could not find such a context.
3285See L<mro>.
3286
5a25739d 3287=item \N in a character class must be a named character: \N{...} in regex;
e0e4a6e3 3288marked by S<<-- HERE> in m/%s/
5a25739d 3289
32a77fbe
FC
3290(F) The new (as of Perl 5.12) meaning of C<\N> as C<[^\n]> is not valid in a
3291bracketed character class, for the same reason that C<.> in a character
3292class loses its specialness: it matches almost everything, which is
3293probably not what you want.
5a25739d 3294
0b4ce96d 3295=item \N{} in character class restricted to one character in regex; marked
e0e4a6e3 3296by S<<-- HERE> in m/%s/
0b4ce96d
FC
3297
3298(F) Named Unicode character escapes C<(\N{...})> may return a
3299multi-character sequence. Such an escape may not be used in
3300a character class, because character classes always match one
3301character of input. Check that the correct escape has been used,
e0e4a6e3 3302and the correct charname handler is in scope. The S<<-- HERE> shows
0b4ce96d
FC
3303whereabouts in the regular expression the problem was discovered.
3304
e0e4a6e3
FC
3305=item \N{NAME} must be resolved by the lexer in regex; marked by