used as an lvalue, which is pretty strange. Perhaps you forgot to
dereference it first. See L<perlfunc/substr>.
-=item Attribute "locked" is deprecated, and will disappear in Perl 5.28
-
-(D deprecated) You have used the attributes pragma to modify the
-"locked" attribute on a code reference. The :locked attribute is
-obsolete, has had no effect since 5005 threads were removed, and
-will be removed in a Perl 5.28.
-
=item Attribute prototype(%s) discards earlier prototype attribute in same sub
(W misc) A sub was declared as sub foo : prototype(A) : prototype(B) {}, for
example. Since each sub can only have one prototype, the earlier
declaration(s) are discarded while the last one is applied.
-=item Attribute "unique" is deprecated, and will disappear in Perl 5.28
-
-(D deprecated) You have used the attributes pragma to modify
-the "unique" attribute on an array, hash or scalar reference.
-The :unique attribute has had no effect since Perl 5.8.8, and
-will be removed in a Perl 5.28.
-
=item av_reify called on tied array
(S debugging) This indicates that something went wrong and Perl got I<very>
issued on exit from the C<default> block, so you won't get the
error if you use an explicit C<continue>.)
+=item Can't determine class of operator %s, assuming BASEOP
+
+(S) This warning indicates something wrong in the internals of perl.
+Perl was trying to find the class (e.g. LISTOP) of a particular OP,
+and was unable to do so. This is likely to be due to a bug in the perl
+internals, or due to a bug in XS code which manipulates perl optrees.
+
=item Can't do inplace edit: %s is not a regular file
(S inplace) You tried to use the B<-i> switch on a special file, such as
See L<perlsub/"Constant Functions"> and L<constant>.
=item Constants from lexical variables potentially modified elsewhere are
-deprecated
+deprecated. This will not be allowed in Perl 5.32
(D deprecated) You wrote something like
the variable itself, rather than its value, so future changes to the
variable are reflected in the subroutine's return value.
-This usage is deprecated, because the behavior is likely to change
-in a future version of Perl.
+This usage is deprecated, and will no longer be allowed in Perl 5.32,
+making it possible to change the behavior in the future.
If you intended for the subroutine to be eligible for inlining, then
make sure the variable is not referenced elsewhere, possibly by
(F) You said something like "use Module 42" but in the Module file
there are neither package declarations nor a C<$VERSION>.
-=item delete argument is index/value array slice, use array slice
-
-(F) You used index/value array slice syntax (C<%array[...]>) as
-the argument to C<delete>. You probably meant C<@array[...]> with
-an @ symbol instead.
-
-=item delete argument is key/value hash slice, use hash slice
-
-(F) You used key/value hash slice syntax (C<%hash{...}>) as the argument to
-C<delete>. You probably meant C<@hash{...}> with an @ symbol instead.
-
=item delete argument is not a HASH or ARRAY element or slice
(F) The argument to C<delete> must be either a hash or array element,
@foo[$bar, $baz, $xyzzy]
@{$ref->[12]}{"susie", "queue"}
+or a hash key/value or array index/value slice, such as:
+
+ %foo[$bar, $baz, $xyzzy]
+ %{$ref->[12]}{"susie", "queue"}
+
=item Delimiter for here document is too long
(F) In a here document construct like C<<<FOO>, the label C<FOO> is too
long for Perl to handle. You have to be seriously twisted to write code
that triggers this error.
-=item Deprecated use of my() in false conditional
+=item Deprecated use of my() in false conditional. This will be a fatal error in Perl 5.30
(D deprecated) You used a declaration similar to C<my $x if 0>. There
has been a long-standing bug in Perl that causes a lexical variable
sub f { state $x; return $x++ }
+This use of C<my()> in a false conditional has been deprecated since
+Perl 5.10, and it will become a fatal error in Perl 5.30.
+
=item DESTROY created new reference to dead object '%s'
(F) A DESTROY() method created a new reference to the object which is
(F) You cannot put a repeat count of any kind right after the '/' code.
See L<perlfunc/pack>.
+=item do "%s" failed, '.' is no longer in @INC; did you mean do "./%s"?
+
+(D deprecated) Previously C< do "somefile"; > would search the current
+directory for the specified file. Since perl v5.26.0, F<.> has been
+removed from C<@INC> by default, so this is no longer true. To search the
+current directory (and only the current directory) you can write
+C< do "./somefile"; >.
+
=item Don't know how to get file name
(P) C<PerlIO_getname>, a perl internal I/O function specific to VMS, was
subroutine or package before the current location. You can use an empty
"sub foo;" or "package FOO;" to enter a "forward" declaration.
-=item dump() better written as CORE::dump()
+=item dump() better written as CORE::dump(). dump() will no longer be available in Perl 5.30
-(W misc) You used the obsolescent C<dump()> built-in function, without fully
-qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
+(D deprecated, misc) You used the obsolescent C<dump()> built-in function,
+without fully qualifying it as C<CORE::dump()>. Maybe it's a typo.
+
+Use of a unqualified C<dump()> was deprecated in Perl 5.8.0, and this
+will not be available in Perl 5.30.
+
+See L<perlfunc/dump>.
=item dump is not supported
(F) The C<exec> function is not implemented on some systems, e.g., Symbian
OS. See L<perlport>.
-=item Execution of %s aborted due to compilation errors.
+=item %sExecution of %s aborted due to compilation errors.
(F) The final summary message when a Perl compilation fails.
Perl. The current valid ones are given in
L<perlrebackslash/\b{}, \b, \B{}, \B>.
-=item %s() is deprecated on :utf8 handles
+=item %s() is deprecated on :utf8 handles. This will be a fatal error in Perl 5.30
(D deprecated) The sysread(), recv(), syswrite() and send() operators are
deprecated on handles that have the C<:utf8> layer, either explicitly, or
Ideally, all of these operators would completely ignore the C<:utf8> state,
working only with bytes, but this would result in silently breaking existing
-code. To avoid this a future version of perl will throw an exception when
-any of sysread(), recv(), syswrite() or send() are called on handle with the
-C<:utf8> layer.
+code.
+
+In Perl 5.30, it will no longer be possible to use sysread(), recv(),
+syswrite() or send() to read or send bytes from/to :utf8 handles.
=item "%s" is more clearly written simply as "%s" in regex; marked by S<<-- HERE> in m/%s/
and which is also portable to platforms running with different character
sets.
+=item $* is no longer supported. Its use will be fatal in Perl 5.30
+
+(D deprecated, syntax) The special variable C<$*>, deprecated in older
+perls, has been removed as of 5.10.0 and is no longer supported. In
+previous versions of perl the use of C<$*> enabled or disabled multi-line
+matching within a string.
+
+Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
+modifiers. You can enable C</m> for a lexical scope (even a whole file)
+with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
+then all regular expressions behaved as if they were written using C</m>.)
+
+Use of this variable will be a fatal error in Perl 5.30.
+
+=item $# is no longer supported. Its use will be fatal in Perl 5.30
+
+(D deprecated, syntax) The special variable C<$#>, deprecated in older
+perls, has been removed as of 5.10.0 and is no longer supported. You
+should use the printf/sprintf functions instead.
+
+Use of this variable will be a fatal error in Perl 5.30.
+
=item '%s' is not a code reference
(W overload) The second (fourth, sixth, ...) argument of
One possible cause is that you set the UTF8 flag yourself for data that
you thought to be in UTF-8 but it wasn't (it was for example legacy
-8-bit data). To guard against this, you can use Encode::decode_utf8.
+8-bit data). To guard against this, you can use C<Encode::decode('UTF-8', ...)>.
If you use the C<:encoding(UTF-8)> PerlIO layer for input, invalid byte
sequences are handled gracefully, but if you use C<:utf8>, the flag is
See also L<Encode/"Handling Malformed Data">.
-=item Malformed UTF-8 character immediately after '%s'
-
-(F) You said C<use utf8>, but the program file doesn't comply with UTF-8
-encoding rules. The message prints out the properly encoded characters
-just before the first bad one. If C<utf8> warnings are enabled, a
-warning is generated that gives more details about the type of
-malformation.
-
=item Malformed UTF-8 returned by \N{%s} immediately after '%s'
(F) The charnames handler returned malformed UTF-8.
(F) You tried to unpack something that didn't comply with UTF-8 encoding
rules and perl was unable to guess how to make more progress.
+=item Malformed UTF-8 string in "%s"
+
+(F) This message indicates a bug either in the Perl core or in XS
+code. Such code was trying to find out if a character, allegedly
+stored internally encoded as UTF-8, was of a given type, such as
+being punctuation or a digit. But the character was not encoded
+in legal UTF-8. The C<%s> is replaced by a string that can be used
+by knowledgeable people to determine what the type being checked
+against was.
+
+Passing malformed strings was deprecated in Perl 5.18, and
+became fatal in Perl 5.26.
+
=item Malformed UTF-16 surrogate
(F) Perl thought it was reading UTF-16 encoded character data but while
(W syntax) An underscore (underbar) in a numeric constant did not
separate two digits.
+=item Missing argument for %n in %s
+
+(F) A C<%n> was used in a format string with no corresponding argument for
+perl to write the current string length to.
+
=item Missing argument in %s
(W missing) You called a function with fewer arguments than other
(4294967295) and therefore non-portable between systems. See
L<perlport> for more on portability concerns.
-=item Odd name/value argument for subroutine
+=item Odd name/value argument for subroutine '%s'
(F) A subroutine using a slurpy hash parameter in its signature
received an odd number of arguments to populate the hash. It requires
the arguments to be paired, with the same number of keys as values.
-The caller of the subroutine is presumably at fault. Inconveniently,
-this error will be reported at the location of the subroutine, not that
-of the caller.
+The caller of the subroutine is presumably at fault.
+
+The message attempts to include the name of the called subroutine. If the
+subroutine has been aliased, the subroutine's original name will be shown,
+regardless of what name the caller used.
=item Odd number of arguments for overload::constant
(S internal) An internal warning that the grammar is screwed up.
-=item Opening dirhandle %s also as a file. This will be a fatal error in Perl 5.28
+=item Cannot open %s as a filehandle: it is already open as a dirhandle
-(D io, deprecated) You used open() to associate a filehandle to
+(F) You tried to use open() to associate a filehandle to
a symbol (glob or scalar) that already holds a dirhandle.
-Although legal, this idiom might render your code confusing
-and this was deprecated in Perl 5.10. In Perl 5.28, this
-will be a fatal error.
+This idiom might render your code confusing
+and this was deprecated in Perl 5.10. As of Perl 5.28, this
+is a fatal error.
-=item Opening filehandle %s also as a directory. This will be a fatal error in Perl 5.28
+=item Cannot open %s as a dirhandle: it is already open as a filehandle
-(D io, deprecated) You used opendir() to associate a dirhandle to
+(F) You tried to use opendir() to associate a dirhandle to
a symbol (glob or scalar) that already holds a filehandle.
-Although legal, this idiom might render your code confusing
-and this was deprecated in Perl 5.10. In Perl 5.28, this
-will be a fatal error.
+This idiom might render your code confusing
+and this was deprecated in Perl 5.10. As of Perl 5.28, this
+is a fatal error.
=item Operand with no preceding operator in regex; marked by S<<-- HERE> in
m/%s/
forget to check the return value of your socket() call? See
L<perlfunc/setsockopt>.
-=item Setting $/ to a reference to %s as a form of slurp is deprecated, treating as undef. This will be fatal in Perl 5.28
+=item Setting $/ to a reference to %s is forbidden
-(D deprecated) You assigned a reference to a scalar to C<$/> where the
+(F) You assigned a reference to a scalar to C<$/> where the
referenced item is not a positive integer. In older perls this B<appeared>
to work the same as setting it to C<undef> but was in fact internally
different, less efficient and with very bad luck could have resulted in
thrown.
You are recommended to change your code to set C<$/> to C<undef> explicitly
-if you wish to slurp the file. In Perl 5.28 assigning C<$/> to a
-reference to an integer which isn't positive will throw a fatal error.
+if you wish to slurp the file. As of Perl 5.28 assigning C<$/> to a
+reference to an integer which isn't positive is a fatal error.
=item Setting $/ to %s reference is forbidden
(F) An ancient error message that almost nobody ever runs into anymore.
But before sort was a keyword, people sometimes used it as a filehandle.
+=item Sorry, hash keys must be smaller than 2**31 bytes
+
+(F) You tried to create a hash containing a very large key, where "very
+large" means that it needs at least 2 gigabytes to store. Unfortunately,
+Perl doesn't yet handle such large hash keys. You should
+reconsider your design to avoid hashing such a long string directly.
+
=item Source filters apply only to byte streams
(F) You tried to activate a source filter (usually by loading a
(F) There has to be at least one argument to syscall() to specify the
system call to call, silly dilly.
-=item Too few arguments for subroutine
+=item Too few arguments for subroutine '%s'
(F) A subroutine using a signature received too few arguments than
required by the signature. The caller of the subroutine is presumably
at fault.
+The message attempts to include the name of the called subroutine. If the
+subroutine has been aliased, the subroutine's original name will be shown,
+regardless of what name the caller used.
+
=item Too late for "-%s" option
(X) The #! line (or local equivalent) in a Perl script contains the
(F) The function requires fewer arguments than you specified.
-=item Too many arguments for subroutine
+=item Too many arguments for subroutine '%s'
(F) A subroutine using a signature received too many arguments than
required by the signature. The caller of the subroutine is presumably
at fault.
+The message attempts to include the name of the called subroutine. If the
+subroutine has been aliased, the subroutine's original name will be shown,
+regardless of what name the caller used.
=item Too many )'s
(A) You've accidentally run your script through B<csh> instead of Perl.
Check the #! line, or manually feed your script into Perl yourself.
-=item Unescaped left brace in regex is deprecated here, passed through in
-regex; marked by S<<-- HERE> in m/%s/
+=item Unescaped left brace in regex is deprecated here (and will be fatal in Perl 5.30), passed through in regex; marked by S<<-- HERE> in m/%s/
(D deprecated, regexp) The simple rule to remember, if you want to
-match a literal C<"{"> character (U+007B C<LEFT CURLY BRACKET>) in a
+match a literal C<{> character (U+007B C<LEFT CURLY BRACKET>) in a
regular expression pattern, is to escape each literal instance of it in
some way. Generally easiest is to precede it with a backslash, like
-C<"\{"> or enclose it in square brackets (C<"[{]">). If the pattern
-delimiters are also braces, any matching right brace (C<"}">) should
+C<\{> or enclose it in square brackets (C<[{]>). If the pattern
+delimiters are also braces, any matching right brace (C<}>) should
also be escaped to avoid confusing the parser, for example,
qr{abc\{def\}ghi}
-Forcing literal C<"{"> characters to be escaped will enable the Perl
+Forcing literal C<{> characters to be escaped will enable the Perl
language to be extended in various ways in future releases. To avoid
needlessly breaking existing code, the restriction is is not enforced in
contexts where there are unlikely to ever be extensions that could
-conflict with the use there of C<"{"> as a literal.
+conflict with the use there of C<{> as a literal.
-In this release of Perl, some literal uses of C<"{"> are fatal, and some
+In this release of Perl, some literal uses of C<{> are fatal, and some
still just deprecated. This is because of an oversight: some uses of a
-literal C<"{"> that should have raised a deprecation warning starting in
+literal C<{> that should have raised a deprecation warning starting in
v5.20 did not warn until v5.26. By making the already-warned uses fatal
now, some of the planned extensions can be made to the language sooner.
+The cases which are still allowed will be fatal in Perl 5.30.
The contexts where no warnings or errors are raised are:
=item *
-as the first character in a pattern, or following C<"^"> indicating to
+as the first character in a pattern, or following C<^> indicating to
anchor the match to the beginning of a line.
=item *
-as the first character following a C<"|"> indicating alternation.
+as the first character following a C<|> indicating alternation.
=item *
also happen if the C<\N{}> is not in the scope of the corresponding
C<S<use charnames>>.
-=item Unknown charname '' is deprecated
-
-(D deprecated) You had a C<\N{}> with nothing between the braces. This
-usage is deprecated, and will be made a syntax error in a future Perl
-version.
-
=item Unknown error
(P) Perl was about to print an error message in C<$@>, but the C<$@> variable
(D deprecated) The C<$[> variable (index of the first element in an array)
is deprecated. See L<perlvar/"$[">.
-=item Use of bare << to mean <<"" is deprecated
+=item Use of bare << to mean <<"" is forbidden
-(D deprecated) You are now encouraged to use the explicitly quoted
+(F) You are now required to use the explicitly quoted
form if you wish to use an empty line as the terminator of the
here-document.
+Use of a bare terminator was deprecated in Perl 5.000, and
+is a fatal error as of Perl 5.28.
+
=item Use of /c modifier is meaningless in s///
(W regexp) You used the /c modifier in a substitution. The /c
use the /g modifier. Currently, /c is meaningful only when /g is
used. (This may change in the future.)
-=item Use of code point 0x%s is deprecated; the permissible max is 0x%s
+=item Use of code point 0x%s is not allowed; the permissible max is 0x%s.
-(D deprecated) You used a code point that will not be allowed in a
-future perl version, because it is too large. Unicode only allows code
-points up to 0x10FFFF, but Perl allows much larger ones. However, the
-largest possible ones break the perl interpreter in some constructs,
-including causing it to hang in a few cases. The known problem areas
-are in C<tr///>, regular expression pattern matching using quantifiers,
-as quote delimiters in C<qI<X>...I<X>> (where I<X> is the C<chr()> of a large
-code point), and as the upper limits in loops.
-There may be other breakages as well. If you get this warning, and
-things aren't working correctly, you probably have found one of these.
+(F) You used a code point that is not allowed, because it is too large.
+Unicode only allows code points up to 0x10FFFF, but Perl allows much
+larger ones. Earlier versions of Perl allowed code points above IV_MAX
+(0x7FFFFFF on 32-bit platforms, 0x7FFFFFFFFFFFFFFF on 64-bit platforms),
+however, this could possibly break the perl interpreter in some constructs,
+including causing it to hang in a few cases.
If your code is to run on various platforms, keep in mind that the upper
limit depends on the platform. It is much larger on 64-bit word sizes
than 32-bit ones.
-=item Use of comma-less variable list is deprecated
-
-(D deprecated) The values you give to a format should be
-separated by commas, not just aligned on a line.
+The use of out of range code points was deprecated in Perl 5.24, and
+became a fatal error in Perl 5.28.
=item Use of each() on hash after insertion without resetting hash iterator results in undefined behavior
(D deprecated) Using C<goto> to jump from an outer scope into an inner
scope is deprecated and should be avoided.
-=item Use of inherited AUTOLOAD for non-method %s() is deprecated
+This was deprecated in Perl 5.12.
-(D deprecated) As an (ahem) accidental feature, C<AUTOLOAD>
-subroutines are looked up as methods (using the C<@ISA> hierarchy)
-even when the subroutines to be autoloaded were called as plain
-functions (e.g. C<Foo::bar()>), not as methods (e.g. C<< Foo->bar() >> or
-C<< $obj->bar() >>).
+=item Use of inherited AUTOLOAD for non-method %s::%s() is no longer allowed
-This bug will be rectified in future by using method lookup only for
-methods' C<AUTOLOAD>s. However, there is a significant base of existing
-code that may be using the old behavior. So, as an interim step, Perl
-currently issues an optional warning when non-methods use inherited
-C<AUTOLOAD>s.
+(F) As an accidental feature, C<AUTOLOAD> subroutines were looked up as
+methods (using the C<@ISA> hierarchy), even when the subroutines to be
+autoloaded were called as plain functions (e.g. C<Foo::bar()>), not as
+methods (e.g. C<< Foo->bar() >> or C<< $obj->bar() >>).
-The simple rule is: Inheritance will not work when autoloading
-non-methods. The simple fix for old code is: In any module that used
-to depend on inheriting C<AUTOLOAD> for non-methods from a base class
-named C<BaseClass>, execute C<*AUTOLOAD = \&BaseClass::AUTOLOAD> during
-startup.
-
-In code that currently says C<use AutoLoader; @ISA = qw(AutoLoader);>
-you should remove AutoLoader from @ISA and change C<use AutoLoader;> to
-C<use AutoLoader 'AUTOLOAD';>.
+This was deprecated in Perl 5.004, and was made fatal in Perl 5.28.
=item Use of %s in printf format not supported
(F) You attempted to use a feature of printf that is accessible from
only C. This usually means there's a better way to do it in Perl.
-=item Use of %s is deprecated
-
-(D deprecated) The construct indicated is no longer recommended for use,
-generally because there's a better way to do it, and also because the
-old way has bad side effects.
-
=item Use of -l on filehandle%s
(W io) A filehandle represents an opened file, and when you opened the file
See the explanation under L<perlvar/$_>.
=item Use of strings with code points over 0xFF as arguments to %s
-operator is deprecated
+operator is not allowed
-(D deprecated) You tried to use one of the string bitwise operators
+(F) You tried to use one of the string bitwise operators
(C<&> or C<|> or C<^> or C<~>) on a string containing a code point over
0xFF. The string bitwise operators treat their operands as strings of
bytes, and values beyond 0xFF are nonsensical in this context.
+This became fatal in Perl 5.28.
+
+=item Use of strings with code points over 0xFF as arguments to C<vec>
+is deprecated. This will be a fatal error in Perl 5.32
+
+(D deprecated) You tried to use L<C<vec>|perlfunc/vec EXPR,OFFSET,BITS>
+on a string containing a code point over 0xFF, which is nonsensical here.
+
+Such usage will be a fatal error in Perl 5.32.
+
=item Use of tainted arguments in %s is deprecated
(W taint, deprecated) You have supplied C<system()> or C<exec()> with multiple
arguments. See L<perlsec>.
=item Use of unassigned code point or non-standalone grapheme for a
-delimiter will be a fatal error starting in Perl v5.30
+delimiter will be a fatal error starting in Perl 5.30
(D deprecated)
A grapheme is what appears to a native-speaker of a language to be a