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01784f0d AD |
1 | =head1 NAME |
2 | ||
3 | perldelta - what's new for perl5.005 | |
4 | ||
5 | =head1 DESCRIPTION | |
6 | ||
7 | This document describes differences between the 5.004 release and this one. | |
8 | ||
429b3afa | 9 | [XXX this needs more verbose summaries of the sub topics, instead of just |
4fe4fdb3 | 10 | the "See foo." Scheduled for a second iteration. GSAR] |
429b3afa GS |
11 | |
12 | =head1 About the new versioning system | |
13 | ||
01784f0d AD |
14 | =head1 Incompatible Changes |
15 | ||
429b3afa GS |
16 | =head2 WARNING: This version is not binary compatible with Perl 5.004. |
17 | ||
18 | Starting with Perl 5.004_50 there were many deep and far-reaching changes | |
19 | to the language internals. If you have dynamically loaded extensions | |
20 | that you built under perl 5.003 or 5.004, you can continue to use them | |
21 | with 5.004, but you will need to rebuild and reinstall those extensions | |
22 | to use them 5.005. See L<INSTALL> for detailed instructions on how to | |
23 | upgrade. | |
24 | ||
7ea97eb9 | 25 | =head2 Default installation structure has changed |
429b3afa | 26 | |
7ea97eb9 AD |
27 | The new Configure defaults are designed to allow a smooth upgrade from |
28 | 5.004 to 5.005, but you should read L<INSTALL> for a detailed | |
29 | discussion of the changes in order to adapt them to your system. | |
429b3afa GS |
30 | |
31 | =head2 Perl Source Compatibility | |
32 | ||
33 | When none of the experimental features are enabled, there should be | |
34 | no user-visible Perl source compatibility issue. | |
35 | ||
36 | If threads are enabled, then some caveats apply. C<@_> and C<$_> become | |
37 | lexical variables. The effect of this should be largely transparent to | |
38 | the user, but there are some boundary conditions under which user will | |
39 | need to be aware of the issues. [XXX Add e.g. here.] | |
40 | ||
fe61ab85 GS |
41 | Some new keywords have been introduced. These are generally expected to |
42 | have very little impact on compatibility. See L</New C<INIT> keyword>, | |
43 | L</New C<lock> keyword>, and L</New C<qr//> operator>. | |
44 | ||
45 | Certain barewords are now reserved. Use of these will provoke a warning | |
46 | if you have asked for them with the C<-w> switch. | |
47 | See L</C<our> is now a reserved word>. | |
48 | ||
429b3afa GS |
49 | =head2 C Source Compatibility |
50 | ||
51 | =item Core sources now require ANSI C compiler | |
52 | ||
53 | =item Enabling threads has source compatibility issues | |
54 | ||
55 | =head2 Binary Compatibility | |
56 | ||
57 | This version is NOT binary compatible with older versions. All extensions | |
58 | will need to be recompiled. | |
59 | ||
60 | =head2 Security fixes may affect compatibility | |
61 | ||
62 | A few taint leaks and taint omissions have been corrected. This may lead | |
63 | to "failure" of scripts that used to work with older versions. Compiling | |
64 | with -DINCOMPLETE_TAINTS provides a perl with minimal amounts of changes | |
65 | to the tainting behavior. But note that the resulting perl will have | |
66 | known insecurities. | |
67 | ||
68 | Oneliners with the C<-e> switch do not create temporary files anymore. | |
69 | ||
70 | =head2 Relaxed new mandatory warnings introduced in 5.004 | |
71 | ||
fe61ab85 | 72 | Many new warnings that were introduced in 5.004 have been made |
429b3afa GS |
73 | optional. Some of these warnings are still present, but perl's new |
74 | features make them less often a problem. See L<New Diagnostics>. | |
75 | ||
76 | =head2 Licensing | |
77 | ||
fe61ab85 | 78 | Perl has a new Social Contract for contributors. See F<Porting/Contract>. |
429b3afa | 79 | |
fe61ab85 GS |
80 | The license included in much of the Perl documentation has changed. |
81 | [XXX See where?] | |
429b3afa | 82 | |
01784f0d AD |
83 | =head1 Core Changes |
84 | ||
01784f0d | 85 | |
429b3afa GS |
86 | =head2 Threads |
87 | ||
88 | WARNING: Threading is considered an experimental feature. Details of the | |
89 | implementation may change without notice. There are known limitations | |
fe61ab85 | 90 | and and some bugs. |
429b3afa GS |
91 | |
92 | See L<README.threads>. | |
93 | ||
94 | =head2 Compiler | |
95 | ||
96 | WARNING: The Compiler and related tools are considered experimental. | |
97 | Features may change without notice, and there are known limitations | |
98 | and bugs. | |
99 | ||
fe61ab85 GS |
100 | The Compiler produces three different types of transformations of a |
101 | perl program. The C backend generates C code that captures perl's state | |
102 | just before execution begins. It eliminates the compile-time overheads | |
103 | of the regular perl interpreter, but the run-time performance remains | |
104 | comparatively the same. The CC backend generates optimized C code | |
105 | equivivalent to the code path at run-time. The CC backend has greater | |
106 | potential for big optimizations, but only a few optimizations are | |
107 | implemented currently. The Bytecode backend generates a platform | |
108 | independent bytecode representation of the interpreter's state | |
109 | just before execution. Thus, the Bytecode back end also eliminates | |
110 | much of the compilation overhead of the interpreter. | |
111 | ||
112 | The compiler comes with several valuable utilities. | |
113 | ||
114 | C<B::Lint> is an experimental module to detect and warn about suspicious | |
115 | code, especially the cases that the C<-w> switch does not detect. | |
116 | ||
117 | C<B::Deparse> can be used to demystify perl code, and understand | |
118 | how perl optimizes certain constructs. | |
119 | ||
120 | C<B::Xref> generates cross reference reports of all definition and use | |
121 | of variables, subroutines and formats in a program. | |
429b3afa | 122 | |
fe61ab85 GS |
123 | C<B::Showlex> show the lexical variables used by a subroutine or file |
124 | at a glance. | |
125 | ||
126 | C<perlcc> is a simple frontend for compiling perl. | |
429b3afa GS |
127 | |
128 | See C<ext/B/README>. | |
129 | ||
130 | =head2 Regular Expressions | |
131 | ||
132 | See L<perlre> and L<perlop>. | |
133 | ||
134 | =head2 Improved malloc() | |
135 | ||
136 | See banner at the beginning of C<malloc.c> for details. | |
137 | ||
138 | =head2 Quicksort is internally implemented | |
139 | ||
140 | See C<perlfunc/sort>. | |
141 | ||
142 | =head2 Reliable signals | |
143 | ||
fe61ab85 GS |
144 | Two kinds. |
145 | ||
146 | Via C<Thread::Signal>. | |
429b3afa | 147 | |
fe61ab85 | 148 | Via switched runtime op loop. [XXX Not yet available.] |
429b3afa GS |
149 | |
150 | =head2 Reliable stack pointers | |
151 | ||
fe61ab85 | 152 | The internals now reallocate the perl stack only at predictable times. |
429b3afa GS |
153 | In particular, magic calls never trigger reallocations of the stack, |
154 | because all reentrancy of the runtime is handled using a "stack of stacks". | |
fe61ab85 GS |
155 | This should improve reliability of cached stack pointers in the internals |
156 | and in XSUBs. | |
429b3afa | 157 | |
407eff0f | 158 | =head2 Behavior of local() on array and hash elements is now well-defined |
429b3afa | 159 | |
407eff0f | 160 | See L<perlsub/"Temporary Values via local()">. |
429b3afa GS |
161 | |
162 | =head2 C<%!> is transparently tied to the L<Errno> module | |
163 | ||
fe61ab85 | 164 | See L<perlvar>, and L<Errno>. |
429b3afa GS |
165 | |
166 | =head2 Pseudo-hashes are supported | |
167 | ||
168 | See L<perlref>. | |
169 | ||
170 | =head2 C<EXPR foreach EXPR> is supported | |
171 | ||
172 | See L<perlsyn>. | |
173 | ||
429b3afa GS |
174 | =head2 Keywords can be globally overridden |
175 | ||
176 | See L<perlsub>. | |
177 | ||
178 | =head2 C<$^E> is meaningful on Win32 | |
179 | ||
180 | See L<perlvar>. | |
181 | ||
182 | =head2 C<foreach (1..1000000)> optimized | |
183 | ||
184 | C<foreach (1..1000000)> is now optimized into a counting loop. It does | |
185 | not try to allocate a 1000000-size list anymore. | |
186 | ||
187 | =head2 C<Foo::> can be used as implicitly quoted package name | |
188 | ||
189 | [XXX See what?] | |
190 | ||
191 | =head2 C<exists $Foo::{Bar::}> tests existence of a package | |
192 | ||
193 | [XXX See what?] | |
194 | ||
195 | =head2 Better locale support | |
196 | ||
197 | See L<perllocale>. | |
198 | ||
7ea97eb9 | 199 | =head2 Experimental support for 64-bit platforms |
429b3afa | 200 | |
7ea97eb9 AD |
201 | Perl5 has always had 64-bit support on systems with 64-bit longs. |
202 | Starting with 5.005, the beginnings of experimental support for systems | |
203 | with 32-bit long and 64-bit 'long long' integers has been added. | |
204 | If you add -DUSE_LONG_LONG to your ccflags in config.sh (or manually | |
205 | define it in perl.h) then perl will be built with 'long long' support. | |
206 | There will be many compiler warnings, and the resultant perl may not | |
207 | work on all systems. There are many other issues related to | |
208 | third-party extensions and libraries. This option exists to allow | |
209 | people to work on those issues. | |
429b3afa GS |
210 | |
211 | =head2 prototype() returns useful results on builtins | |
212 | ||
213 | See L<perlfunc/prototype>. | |
214 | ||
1a159553 GS |
215 | =head2 Extended support for exception handling |
216 | ||
217 | C<die()> now accepts a reference value, and C<$@> gets set to that | |
218 | value in exception traps. This makes it possible to propagate | |
219 | exception objects. See L<perlfunc/eval>. [XXX there's nothing | |
220 | about this in perlfunc/eval yet.] | |
221 | ||
429b3afa GS |
222 | =head2 Re-blessing in DESTROY() supported for chaining DESTROY() methods |
223 | ||
224 | See L<perlobj/Destructors>. | |
225 | ||
226 | =head2 All C<printf> format conversions are handled internally | |
227 | ||
228 | See L<perlfunc/printf>. | |
229 | ||
230 | =head2 New C<INIT> keyword | |
231 | ||
fe61ab85 GS |
232 | C<INIT> subs are like C<BEGIN> and C<END>, but they get run just before |
233 | the perl runtime begins execution. e.g., the Perl Compiler makes use of | |
234 | C<INIT> blocks to initialize and resolve pointers to XSUBs. | |
429b3afa GS |
235 | |
236 | [XXX Needs to be documented in perlsub or perlmod.] | |
237 | ||
238 | =head2 New C<lock> keyword | |
239 | ||
fe61ab85 GS |
240 | The C<lock> keyword is the fundamental synchronization primitive |
241 | in threaded perl. When threads are not enabled, it is currently a noop. | |
242 | ||
429b3afa GS |
243 | To minimize impact on source compatibility this keyword is "weak", i.e., any |
244 | user-defined subroutine of the same name overrides it, unless a C<use Thread> | |
245 | has been seen. | |
246 | ||
fe61ab85 GS |
247 | =head2 New C<qr//> operator |
248 | ||
249 | The C<qr//> operator, which is syntactically similar to the other quote-like | |
0a92e3a8 | 250 | operators, is used to create precompiled regular expressions. This compiled |
fe61ab85 | 251 | form can now be explicitly passed around in variables, and interpolated in |
0a92e3a8 | 252 | other regular expressions. See L<perlop>. |
fe61ab85 GS |
253 | |
254 | =head2 C<our> is now a reserved word | |
255 | ||
429b3afa GS |
256 | =head2 Tied arrays are now fully supported |
257 | ||
258 | See L<Tie::Array>. | |
259 | ||
260 | =head2 Tied handles support is better | |
261 | ||
262 | Several missing hooks have been added. There is also a new base class for | |
263 | TIEARRAY implementations. See L<Tie::Array>. | |
264 | ||
6bb4e6d4 GS |
265 | =head2 4th argument to substr |
266 | ||
267 | substr() can now both return and replace in one operation. The optional | |
268 | 4th argument is the replacement string. See L<perlfunc/substr>. | |
269 | ||
270 | =head2 Negative LENGTH argument to splice | |
271 | ||
272 | Splice() with a negative LENGTH argument now work similar to what the | |
273 | LENGTH did for substr(). Previously a negative LENGTH was treated as | |
274 | 0. See L<perlfunc/splice>. | |
275 | ||
407eff0f SM |
276 | =head2 Magic lvalues are now more magical |
277 | ||
278 | When you say something like C<substr($x, 5) = "hi">, the scalar returned | |
279 | by substr() is special, in that any modifications to it affect $x. | |
280 | (This is called a 'magic lvalue' because an 'lvalue' is something on | |
281 | the left side of an assignment.) Normally, this is exactly what you | |
282 | would expect to happen, but Perl uses the same magic if you use substr(), | |
283 | pos(), or vec() in a context where they might be modified, like taking | |
284 | a reference with C<\> or as an argument to a sub that modifies C<@_>. | |
285 | In previous versions, this 'magic' only went one way, but now changes | |
286 | to the scalar the magic refers to ($x in the above example) affect the | |
287 | magic lvalue too. For instance, this code now acts differently: | |
288 | ||
289 | $x = "hello"; | |
290 | sub printit { | |
291 | $x = "g'bye"; | |
292 | print $_[0], "\n"; | |
293 | } | |
294 | printit(substr($x, 0, 5)); | |
295 | ||
296 | In previous versions, this would print "hello", but it now prints "g'bye". | |
297 | ||
429b3afa GS |
298 | |
299 | =head1 Supported Platforms | |
300 | ||
301 | Configure has many incremental improvements. Site-wide policy for building | |
fe61ab85 | 302 | perl can now be made persistent, via Policy.sh. Configure also records |
7ea97eb9 | 303 | the command-line arguments used in F<config.sh>. |
429b3afa GS |
304 | |
305 | =head2 New Platforms | |
306 | ||
307 | BeOS is now supported. See L<README.beos>. | |
308 | ||
309 | DOS is now supported under the DJGPP tools. See L<README.dos>. | |
310 | ||
1d84e8df JH |
311 | MPE/iX is now supported. See L<README.mpeix>. |
312 | ||
429b3afa GS |
313 | =head2 Changes in existing support |
314 | ||
315 | Win32 support has been vastly enhanced. Support for Perl Object, a C++ | |
316 | encapsulation of Perl. GCC and EGCS are now supported on Win32. | |
317 | [XXX Perl Object needs a big explanation elsewhere, and a pointer to | |
318 | that location here.] | |
319 | ||
320 | VMS configuration system has been rewritten. See L<README.vms>. | |
321 | ||
322 | OpenBSD better supported. [XXX what others?] | |
323 | ||
324 | =head1 Modules and Pragmata | |
325 | ||
326 | =head2 New Modules | |
327 | ||
328 | =over | |
329 | ||
330 | =item B | |
331 | ||
332 | Perl compiler and tools. See [XXX what?]. | |
333 | ||
334 | =item Data::Dumper | |
335 | ||
336 | A module to pretty print Perl data. See L<Data::Dumper>. | |
337 | ||
338 | =item Errno | |
339 | ||
340 | A module to look up errors more conveniently. See L<Errno>. | |
341 | ||
342 | =item File::Spec | |
343 | ||
344 | A portable API for file operations. | |
345 | ||
346 | =item ExtUtils::Installed | |
347 | ||
348 | Query and manage installed modules. | |
349 | ||
350 | =item ExtUtils::Packlist | |
351 | ||
352 | Manipulate .packlist files. | |
353 | ||
354 | =item Fatal | |
355 | ||
356 | Make functions/builtins succeed or die. | |
357 | ||
358 | =item IPC::SysV | |
359 | ||
360 | Constants and other support infrastructure for System V IPC operations | |
361 | in perl. | |
362 | ||
363 | =item Test | |
364 | ||
365 | A framework for writing testsuites. | |
01784f0d | 366 | |
429b3afa GS |
367 | =item Tie::Array |
368 | ||
369 | Base class for tied arrays. | |
370 | ||
371 | =item Tie::Handle | |
372 | ||
373 | Base class for tied handles. | |
374 | ||
375 | =item Thread | |
376 | ||
377 | Perl thread creation, manipulation, and support. | |
378 | ||
379 | =item attrs | |
380 | ||
381 | Set subroutine attributes. | |
382 | ||
383 | =item fields | |
384 | ||
385 | Compile-time class fields. | |
386 | ||
387 | =item re | |
388 | ||
389 | Various pragmata to control behavior of regular expressions. | |
390 | ||
391 | =back | |
392 | ||
393 | =head2 Changes in existing modules | |
394 | ||
395 | =over | |
396 | ||
397 | =item CGI | |
398 | ||
399 | CGI has been updated to version 2.42. | |
400 | ||
401 | =item POSIX | |
402 | ||
403 | POSIX now has its own platform-specific hints files. | |
404 | ||
405 | =item DB_File | |
406 | ||
407 | DB_File supports version 2.x of Berkeley DB. See C<ext/DB_File/Changes>. | |
408 | ||
409 | =item MakeMaker | |
410 | ||
411 | MakeMaker now supports writing empty makefiles, provides a way to | |
412 | specify that site umask() policy should be honored. There is also | |
413 | better support for manipulation of .packlist files, and getting | |
414 | information about installed modules. | |
415 | ||
7ea97eb9 AD |
416 | Extensions that have both architecture-dependent and |
417 | architecture-independent files are now always installed completely in | |
418 | the architecture-dependent locations. Previously, the shareable parts | |
419 | were shared both across architectures and across perl versions and were | |
420 | therefore liable to be overwritten with newer versions that might have | |
421 | subtle incompatibilities. | |
422 | ||
429b3afa GS |
423 | =item CPAN |
424 | ||
425 | [XXX What?] | |
426 | ||
427 | =item Cwd | |
428 | ||
429 | Cwd::cwd is faster on most platforms. | |
430 | ||
431 | =item Benchmark | |
432 | ||
433 | Keeps better time. | |
434 | ||
435 | =back | |
01784f0d AD |
436 | |
437 | =head1 Utility Changes | |
438 | ||
429b3afa GS |
439 | h2ph and related utilities have been vastly overhauled. |
440 | ||
441 | perlcc, a new experimental front end for the compiler is available. | |
442 | ||
7ea97eb9 AD |
443 | The crude GNU configure emulator is now called configure.gnu. |
444 | ||
429b3afa GS |
445 | =head1 API Changes |
446 | ||
447 | =head2 Incompatible Changes | |
448 | ||
449 | =head2 Deprecations, Extensions | |
450 | ||
451 | =head2 C++ Support | |
01784f0d AD |
452 | |
453 | =head1 Documentation Changes | |
454 | ||
429b3afa GS |
455 | Config.pm now has a glossary of variables. |
456 | ||
457 | Porting/patching.pod has detailed instructions on how to create and | |
458 | submit patches for perl. | |
459 | ||
460 | =head1 New Diagnostics | |
461 | ||
462 | =over | |
463 | ||
464 | =item Ambiguous call resolved as CORE::%s(), qualify as such or use & | |
465 | ||
466 | (W) A subroutine you have declared has the same name as a Perl keyword, | |
467 | and you have used the name without qualification for calling one or the | |
468 | other. Perl decided to call the builtin because the subroutine is | |
469 | not imported. | |
470 | ||
471 | To force interpretation as a subroutine call, either put an ampersand | |
472 | before the subroutine name, or qualify the name with its package. | |
473 | Alternatively, you can import the subroutine (or pretend that it's | |
474 | imported with the C<use subs> pragma). | |
475 | ||
476 | To silently interpret it as the Perl operator, use the C<CORE::> prefix | |
477 | on the operator (e.g. C<CORE::log($x)>) or by declaring the subroutine | |
478 | to be an object method (see L<attrs>). | |
479 | ||
480 | =item Bad index while coercing array into hash | |
481 | ||
482 | (F) The index looked up in the hash found as the 0'th element of a | |
483 | pseudo-hash is not legal. Index values must be at 1 or greater. | |
484 | See L<perlref>. | |
485 | ||
486 | =item Bareword "%s" refers to nonexistent package | |
487 | ||
488 | (W) You used a qualified bareword of the form C<Foo::>, but | |
489 | the compiler saw no other uses of that namespace before that point. | |
490 | Perhaps you need to predeclare a package? | |
491 | ||
492 | =item Can't call method "%s" on an undefined value | |
493 | ||
494 | (F) You used the syntax of a method call, but the slot filled by the | |
495 | object reference or package name contains an undefined value. | |
496 | Something like this will reproduce the error: | |
497 | ||
498 | $BADREF = 42; | |
499 | process $BADREF 1,2,3; | |
500 | $BADREF->process(1,2,3); | |
501 | ||
502 | =item Can't coerce array into hash | |
503 | ||
504 | (F) You used an array where a hash was expected, but the array has no | |
505 | information on how to map from keys to array indices. You can do that | |
506 | only with arrays that have a hash reference at index 0. | |
507 | ||
508 | =item Can't goto subroutine from an eval-string | |
509 | ||
510 | (F) The "goto subroutine" call can't be used to jump out of an eval "string". | |
511 | (You can use it to jump out of an eval {BLOCK}, but you probably don't want to.) | |
512 | ||
0ebe0038 SM |
513 | =item Can't localize pseudo-hash element |
514 | ||
515 | (F) You said something like C<local $ar-E<gt>{'key'}>, where $ar is | |
516 | a reference to a pseudo-hash. That hasn't been implemented yet, but | |
517 | you can get a similar effect by localizing the corresponding array | |
518 | element directly -- C<local $ar-E<gt>[$ar-E<gt>[0]{'key'}]>. | |
519 | ||
429b3afa GS |
520 | =item Can't use %%! because Errno.pm is not available |
521 | ||
522 | (F) The first time the %! hash is used, perl automatically loads the | |
523 | Errno.pm module. The Errno module is expected to tie the %! hash to | |
524 | provide symbolic names for C<$!> errno values. | |
525 | ||
429b3afa GS |
526 | =item Cannot find an opnumber for "%s" |
527 | ||
528 | (F) A string of a form C<CORE::word> was given to prototype(), but | |
529 | there is no builtin with the name C<word>. | |
530 | ||
531 | =item Character class syntax [. .] is reserved for future extensions | |
532 | ||
533 | (W) Within regular expression character classes ([]) the syntax beginning | |
534 | with "[." and ending with ".]" is reserved for future extensions. | |
535 | If you need to represent those character sequences inside a regular | |
536 | expression character class, just quote the square brackets with the | |
537 | backslash: "\[." and ".\]". | |
538 | ||
539 | =item Character class syntax [: :] is reserved for future extensions | |
540 | ||
541 | (W) Within regular expression character classes ([]) the syntax beginning | |
542 | with "[:" and ending with ":]" is reserved for future extensions. | |
543 | If you need to represent those character sequences inside a regular | |
544 | expression character class, just quote the square brackets with the | |
545 | backslash: "\[:" and ":\]". | |
546 | ||
547 | =item Character class syntax [= =] is reserved for future extensions | |
548 | ||
549 | (W) Within regular expression character classes ([]) the syntax | |
550 | beginning with "[=" and ending with "=]" is reserved for future extensions. | |
551 | If you need to represent those character sequences inside a regular | |
552 | expression character class, just quote the square brackets with the | |
553 | backslash: "\[=" and "=\]". | |
554 | ||
555 | =item %s: Eval-group in insecure regular expression | |
556 | ||
557 | (F) Perl detected tainted data when trying to compile a regular expression | |
558 | that contains the C<(?{ ... })> zero-width assertion, which is unsafe. | |
559 | See L<perlre/(?{ code })>, and L<perlsec>. | |
560 | ||
561 | =item %s: Eval-group not allowed, use re 'eval' | |
562 | ||
563 | (F) A regular expression contained the C<(?{ ... })> zero-width assertion, | |
564 | but that construct is only allowed when the C<use re 'eval'> pragma is | |
565 | in effect. See L<perlre/(?{ code })>. | |
566 | ||
567 | =item %s: Eval-group not allowed at run time | |
568 | ||
569 | (F) Perl tried to compile a regular expression containing the C<(?{ ... })> | |
570 | zero-width assertion at run time, as it would when the pattern contains | |
571 | interpolated values. Since that is a security risk, it is not allowed. | |
572 | If you insist, you may still do this by explicitly building the pattern | |
573 | from an interpolated string at run time and using that in an eval(). | |
574 | See L<perlre/(?{ code })>. | |
575 | ||
576 | =item Explicit blessing to '' (assuming package main) | |
577 | ||
578 | (W) You are blessing a reference to a zero length string. This has | |
579 | the effect of blessing the reference into the package main. This is | |
580 | usually not what you want. Consider providing a default target | |
581 | package, e.g. bless($ref, $p or 'MyPackage'); | |
582 | ||
583 | =item Illegal hex digit ignored | |
584 | ||
585 | (W) You may have tried to use a character other than 0 - 9 or A - F in a | |
586 | hexadecimal number. Interpretation of the hexadecimal number stopped | |
587 | before the illegal character. | |
588 | ||
589 | =item No such array field | |
590 | ||
591 | (F) You tried to access an array as a hash, but the field name used is | |
592 | not defined. The hash at index 0 should map all valid field names to | |
593 | array indices for that to work. | |
594 | ||
595 | =item No such field "%s" in variable %s of type %s | |
596 | ||
597 | (F) You tried to access a field of a typed variable where the type | |
598 | does not know about the field name. The field names are looked up in | |
599 | the %FIELDS hash in the type package at compile time. The %FIELDS hash | |
600 | is usually set up with the 'fields' pragma. | |
601 | ||
602 | =item Out of memory during ridiculously large request | |
603 | ||
604 | (F) You can't allocate more than 2^31+"small amount" bytes. This error | |
605 | is most likely to be caused by a typo in the Perl program. e.g., C<$arr[time]> | |
606 | instead of C<$arr[$time]>. | |
607 | ||
608 | =item Range iterator outside integer range | |
609 | ||
610 | (F) One (or both) of the numeric arguments to the range operator ".." | |
611 | are outside the range which can be represented by integers internally. | |
612 | One possible workaround is to force Perl to use magical string | |
613 | increment by prepending "0" to your numbers. | |
614 | ||
615 | =item Recursive inheritance detected while looking for method '%s' in package '%s' | |
616 | ||
617 | (F) More than 100 levels of inheritance were encountered while invoking a | |
618 | method. Probably indicates an unintended loop in your inheritance hierarchy. | |
619 | ||
620 | =item Reference found where even-sized list expected | |
621 | ||
622 | (W) You gave a single reference where Perl was expecting a list with | |
623 | an even number of elements (for assignment to a hash). This | |
624 | usually means that you used the anon hash constructor when you meant | |
625 | to use parens. In any case, a hash requires key/value B<pairs>. | |
626 | ||
627 | %hash = { one => 1, two => 2, }; # WRONG | |
628 | %hash = [ qw/ an anon array / ]; # WRONG | |
629 | %hash = ( one => 1, two => 2, ); # right | |
630 | %hash = qw( one 1 two 2 ); # also fine | |
631 | ||
632 | =item Undefined value assigned to typeglob | |
633 | ||
634 | (W) An undefined value was assigned to a typeglob, a la C<*foo = undef>. | |
635 | This does nothing. It's possible that you really mean C<undef *foo>. | |
636 | ||
637 | =item Use of reserved word "%s" is deprecated | |
638 | ||
639 | (D) The indicated bareword is a reserved word. Future versions of perl | |
640 | may use it as a keyword, so you're better off either explicitly quoting | |
641 | the word in a manner appropriate for its context of use, or using a | |
642 | different name altogether. The warning can be suppressed for subroutine | |
643 | names by either adding a C<&> prefix, or using a package qualifier, | |
644 | e.g. C<&our()>, or C<Foo::our()>. | |
645 | ||
646 | =item perl: warning: Setting locale failed. | |
647 | ||
648 | (S) The whole warning message will look something like: | |
649 | ||
650 | perl: warning: Setting locale failed. | |
651 | perl: warning: Please check that your locale settings: | |
652 | LC_ALL = "En_US", | |
653 | LANG = (unset) | |
654 | are supported and installed on your system. | |
655 | perl: warning: Falling back to the standard locale ("C"). | |
656 | ||
657 | Exactly what were the failed locale settings varies. In the above the | |
658 | settings were that the LC_ALL was "En_US" and the LANG had no value. | |
659 | This error means that Perl detected that you and/or your system | |
660 | administrator have set up the so-called variable system but Perl could | |
661 | not use those settings. This was not dead serious, fortunately: there | |
662 | is a "default locale" called "C" that Perl can and will use, the | |
663 | script will be run. Before you really fix the problem, however, you | |
664 | will get the same error message each time you run Perl. How to really | |
665 | fix the problem can be found in L<perllocale> section B<LOCALE PROBLEMS>. | |
666 | ||
667 | =back | |
668 | ||
669 | ||
670 | =head1 Obsolete Diagnostics | |
671 | ||
672 | =over | |
6cc33c6d | 673 | |
429b3afa GS |
674 | =item Can't mktemp() |
675 | ||
676 | (F) The mktemp() routine failed for some reason while trying to process | |
677 | a B<-e> switch. Maybe your /tmp partition is full, or clobbered. | |
678 | ||
679 | =item Can't write to temp file for B<-e>: %s | |
680 | ||
681 | (F) The write routine failed for some reason while trying to process | |
682 | a B<-e> switch. Maybe your /tmp partition is full, or clobbered. | |
683 | ||
684 | =item Cannot open temporary file | |
685 | ||
686 | (F) The create routine failed for some reason while trying to process | |
687 | a B<-e> switch. Maybe your /tmp partition is full, or clobbered. | |
688 | ||
689 | ||
690 | =back | |
691 | ||
01784f0d AD |
692 | =head1 BUGS |
693 | ||
694 | If you find what you think is a bug, you might check the headers of | |
695 | recently posted articles in the comp.lang.perl.misc newsgroup. | |
696 | There may also be information at http://www.perl.com/perl/, the Perl | |
697 | Home Page. | |
698 | ||
699 | If you believe you have an unreported bug, please run the B<perlbug> | |
700 | program included with your release. Make sure you trim your bug down | |
701 | to a tiny but sufficient test case. Your bug report, along with the | |
702 | output of C<perl -V>, will be sent off to <F<perlbug@perl.com>> to be | |
703 | analysed by the Perl porting team. | |
704 | ||
705 | =head1 SEE ALSO | |
706 | ||
707 | The F<Changes> file for exhaustive details on what changed. | |
708 | ||
709 | The F<INSTALL> file for how to build Perl. | |
710 | ||
711 | The F<README> file for general stuff. | |
712 | ||
713 | The F<Artistic> and F<Copying> files for copyright information. | |
714 | ||
715 | =head1 HISTORY | |
429b3afa GS |
716 | |
717 | =cut |