3 perldelta - what is new for perl v5.11.3
7 This document describes differences between the 5.11.2 release and
10 If you are upgrading from an earlier release such as 5.11.1, first read
11 the L<perl5112delta>, which describes differences between 5.11.1 and
14 =head1 Incompatible Changes
18 =item Filehandles are blessed directly into C<IO::Handle::>, as C<FileHandle> is merely a wrapper around C<IO::Handle>.
20 The previous behaviour was to bless Filehandles into L<FileHandle/>
21 (an empty proxy class) if it was loaded into memory and otherwise
22 to bless them into C<IO::Handle::>.
27 =head1 Core Enhancements
29 =head2 Unicode version
31 Perl is shipped with the latest Unicode version, 5.2, dated October 2009. See
32 L<http://www.unicode.org/versions/Unicode5.2.0> for details about this release
33 of Unicode. See L<perlunicode> for instructions on installing and using
34 older versions of Unicode.
36 =head2 Unicode properties
38 Perl can now handle every Unicode character property. A new pod,
39 L<perluniprops>, lists all available non-Unihan character properties. By
40 default the Unihan properties and certain others (deprecated and Unicode
41 internal-only ones) are not exposed. See below for more details on
42 these; there is also a section in the pod listing them, and why they are
45 Perl now fully supports the Unicode compound-style of using C<=> and C<:>
46 in writing regular expressions: C<\p{property=value}> and
47 C<\p{property:value}> (both of which mean the same thing).
49 Perl now fully supports the Unicode loose matching rules for text
50 between the braces in C<\p{...}> constructs. In addition, Perl also allows
51 underscores between digits of numbers.
53 All the Unicode-defined synonyms for properties and property values are
56 C<qr/\X/>, which matches a Unicode logical character, has been expanded to work
57 better with various Asian languages. It now is defined as an C<extended
58 grapheme cluster>. (See L<http://www.unicode.org/reports/tr29/>).
59 Anything matched by previously will continue to be matched. But in addition:
65 C<\X> will now not break apart a C<S<CR LF>> sequence.
69 C<\X> will now match a sequence including the C<ZWJ> and C<ZWNJ> characters.
73 C<\X> will now always match at least one character, including an initial mark.
74 Marks generally come after a base character, but it is possible in Unicode to
75 have them in isolation, and C<\X> will now handle that case, for example at the
76 beginning of a line or after a C<ZWSP>.
80 C<\X> will now match a (Korean) Hangul syllable sequence, and the Thai and Lao
85 Otherwise, this change should be transparent for the non-affected languages.
87 C<\p{...}> matches using the Canonical_Combining_Class property were
88 completely broken in previous Perls. This is now fixed.
90 In previous Perls, the Unicode C<Decomposition_Type=Compat> property and a
91 Perl extension had the same name, which led to neither matching all the
92 correct values (with more than 100 mistakes in one, and several thousand
93 in the other). The Perl extension has now been renamed to be
94 C<Decomposition_Type=Noncanonical> (short: C<dt=noncanon>). It has the same
95 meaning as was previously intended, namely the union of all the
96 non-canonical Decomposition types, with Unicode C<Compat> being just one of
99 C<\p{Uppercase}> and C<\p{Lowercase}> have been brought into line with the
100 Unicode definitions. This means they each match a few more characters
103 C<\p{Cntrl}> now matches the same characters as C<\p{Control}>. This means it
104 no longer will match Private Use (gc=co), Surrogates (gc=cs), nor Format
105 (gc=cf) code points. The Format code points represent the biggest
106 possible problem. All but 36 of them are either officially deprecated
107 or strongly discouraged from being used. Of those 36, likely the most
108 widely used are the soft hyphen (U+00AD), and BOM, ZWSP, ZWNJ, WJ, and
109 similar, plus Bi-directional controls.
111 C<\p{Alpha}> now matches the same characters as C<\p{Alphabetic}>. The Perl
112 definition included a number of things that aren't really alpha (all
113 marks), while omitting many that were. As a direct consequence, the
114 definitions of C<\p{Alnum}> and C<\p{Word}> which depend on Alpha also change.
116 C<\p{Word}> also now doesn't match certain characters it wasn't supposed
117 to, such as fractions.
119 C<\p{Print}> no longer matches the line control characters: Tab, LF, CR,
120 FF, VT, and NEL. This brings it in line with the documentation.
122 C<\p{Decomposition_Type=Canonical}> now includes the Hangul syllables.
124 The Numeric type property has been extended to include the Unihan
127 There is a new Perl extension, the 'Present_In', or simply 'In',
128 property. This is an extension of the Unicode Age property, but
129 C<\p{In=5.0}> matches any code point whose usage has been determined
130 I<as of> Unicode version 5.0. The C<\p{Age=5.0}> only matches code points
131 added in I<precisely> version 5.0.
133 A number of properties did not have the correct values for unassigned
134 code points. This is now fixed. The affected properties are
135 Bidi_Class, East_Asian_Width, Joining_Type, Decomposition_Type,
136 Hangul_Syllable_Type, Numeric_Type, and Line_Break.
138 The Default_Ignorable_Code_Point, ID_Continue, and ID_Start properties
139 have been updated to their current Unicode definitions.
141 Certain properties that are supposed to be Unicode internal-only were
142 erroneously exposed by previous Perls. Use of these in regular
143 expressions will now generate, if enabled, a deprecated warning message.
144 The properties are: Other_Alphabetic, Other_Default_Ignorable_Code_Point,
145 Other_Grapheme_Extend, Other_ID_Continue, Other_ID_Start, Other_Lowercase,
146 Other_Math, and Other_Uppercase.
148 An installation can now fairly easily change which Unicode properties
149 Perl understands. As mentioned above, certain properties are by default
150 turned off. These include all the Unihan properties (which should be
151 accessible via the CPAN module Unicode::Unihan) and any deprecated or
152 Unicode internal-only property that Perl has never exposed.
154 XXX what does "files in the To directory" mean? -- dagolden, 2009-12-20
156 The files in the C<lib/unicore/To> directory are now more clearly marked as
157 being stable, directly usable by applications. New hash entries in them give
158 the format of the normal entries, which allows for easier machine parsing.
159 Perl can generate files in this directory for any property, though most are
160 suppressed. An installation can choose to change which get written.
161 Instructions are in L<perluniprops>.
163 =head2 Regular Expressions
165 U+0FFFF is now a legal character in regular expressions
167 =head1 Modules and Pragmata
169 =head2 Pragmata Changes
175 Upgraded from version 1.19 to 1.20.
179 This pragma no longer suppresses C<Use of uninitialized value in range (or flip)> warnings. [perl #71204]
183 Upgraded from 1.13 to 1.14. Added the C<unicode_strings> feature:
185 use feature "unicode_strings";
187 This pragma turns on Unicode semantics for the case-changing operations
188 (uc/lc/ucfirst/lcfirst) on strings that don't have the internal UTF-8 flag set,
189 but that contain single-byte characters between 128 and 255.
193 The experimental C<legacy> pragma, introduced in 5.11.2, has been removed,
194 and its functionality replaced by the new feature pragma, C<use feature
199 Upgraded from version 1.74 to 1.75.
203 Upgraded from 1.07 to 1.08. Added new C<warnings::fatal_enabled()> function.
207 =head2 Updated Modules
211 =item C<Archive::Extract>
213 Upgraded from version 0.34 to 0.36.
217 Upgraded from version 1.94_51 to 1.94_53. Includes better bzip2 support,
218 improved FirstTime experience with auto-selection of CPAN mirrors, proper
219 handling of modules removed from the Perl core, and an updated 'cpan'
224 Upgraded from version 0.89_09 to 0.90.
226 =item C<ExtUtils::MakeMaker>
228 Upgraded from version 6.55_02 to 6.56. Adds new BUILD_REQUIRES key to
229 indicate build-only prerequisites. Also adds support for
230 mingw64 and the new "package NAME VERSION" syntax.
234 Upgraded from version 2.08 to 2.08_01.
236 =item C<Module::Build>
238 Upgraded from version 0.35_09 to 0.36. Compared to 0.35, this version has a
239 new 'installdeps' action, supports the PERL_MB_OPT environment variable, adds a
240 'share_dir' property for L<File::ShareDir> support, support the "package NAME
241 VERSION" syntax and has many other enhancements and bug fixes. The
242 'passthrough' style of Module::Build::Compat has been deprecated.
244 =item C<Module::CoreList>
246 Upgraded from version 2.23 to 2.24.
250 Upgraded from version 1.18 to 1.19. Error codes for C<getaddrinfo()> and C<getnameinfo()> are now
255 Upgraded from version 3.10 to 3.13.
259 Upgraded from version 2.19 to 2.20.
263 =head1 Utility Changes
269 No longer reports "Message sent" when it hasn't actually sent the message
273 =head1 Changes to Existing Documentation
275 The Pod specification (L<perlpodspec>) has been updated to bring the
276 specification in line with modern usage already supported by most Pod systems.
277 A parameter string may now follow the format name in a "begin/end" region.
278 Links to URIs with a text description are now allowed. The usage of
279 C<LE<lt>"section"E<gt>> has been marked as deprecated.
281 L<if.pm|if> has been documented in L<perlfunc/use> as a means to get
282 conditional loading of modules despite the implicit BEGIN block around C<use>.
286 =head1 Installation and Configuration Improvements
288 XXX Changes to F<Configure>, F<installperl>, F<installman>, and analogous tools
291 =head2 Configuration improvements
295 =head2 Compilation improvements
297 Make distclean work again
300 =head2 Testing improvements
304 =item It's now possible to override C<PERL5OPT> and friends in F<t/TEST>
308 =head2 Platform Specific Changes
318 Always add a manifest resource to C<perl.exe> to specify the <trustInfo>
319 settings for Windows Vista and later. Without this setting Windows
320 will treat C<perl.exe> as a legacy application and apply various
321 heuristics like redirecting access to protected file system areas
322 (like the "Program Files" folder) to the users "VirtualStore"
323 instead of generating a proper "permission denied" error.
325 For VC8 and VC9 this manifest setting is automatically generated by
326 the compiler/linker (together with the binding information for their
327 respective runtime libraries); for all other compilers we need to
328 embed the manifest resource explicitly in the external resource file.
330 This change also requests the Microsoft Common-Controls version 6.0
331 (themed controls introduced in Windows XP) via the dependency list
332 in the assembly manifest. For VC8 and VC9 this is specified using the
333 C</manifestdependency> linker commandline option instead.
341 =item Enable IPv6 support on cygwin 1.7 and newer
349 =item Make -UDEBUGGING the default on VMS for 5.12.0.
351 Like it has been everywhere else for ages and ages. Also make
352 command-line selection of -UDEBUGGING and -DDEBUGGING work in
353 configure.com; before the only way to turn it off was by saying
354 no in answer to the interactive question.
360 =head1 Selected Bug Fixes
362 XXX Important bug fixes in the core language are summarised here.
363 Bug fixes in files in F<ext/> and F<lib/> are best summarised in
364 L</Modules and Pragmata>.
370 Ensure that pp_qr returns a new regexp SV each time. Resolves RT #69852.
372 Instead of returning a(nother) reference to the (pre-compiled) regexp in the
373 optree, use reg_temp_copy() to create a copy of it, and return a reference to
374 that. This resolves issues about Regexp::DESTROY not being called in a timely
375 fashion (the original bug tracked by RT #69852), as well as bugs related to
376 blessing regexps, and of assigning to regexps, as described in correspondence
379 It transpires that we also need to undo the SvPVX() sharing when ithreads
380 cloning a Regexp SV, because mother_re is set to NULL, instead of a cloned
381 copy of the mother_re. This change might fix bugs with regexps and threads in
382 certain other situations, but as yet neither tests nor bug reports have
383 indicated any problems, so it might not actually be an edge case that it's
388 Several compilation errors and segfaults when perl was built with C<-Dmad> were fixed.
392 Fixes for lexer API changes in 5.11.2 which broke NYTProf's savesrc option.
396 F<-t> should only return TRUE for file handles connected to a TTY
398 The Microsoft C version of isatty() returns TRUE for all
399 character mode devices, including the /dev/null style "nul"
400 device and printers like "lpt1".
404 Fixed a regression caused by commit fafafbaf which caused a panic during parameter passing [perl #70171]
409 On systems which in-place edits without backup files, -i'*' now works as the documentation says it does [perl #70802]
413 Saving and restoring magic flags no longer loses readonly flag.
417 The malformed syntax C<grep EXPR LIST> (note the missing comma) no longer
418 causes abrupt and total failure.
422 Regular expressions compiled with C<qr{}> literals properly set C<$'> when
427 Using named subroutines with C<sort> should no longer lead to bus errors [perl
432 Numerous bugfixes catch small issues caused by the recently-added Lexer API.
436 Smart match against C<@_> sometimes gave false negatives negatives. [perl #71078]
440 C<$@> may now be assigned a read-only value (without error or busting the stack).
444 C<sort> called recursively from within an active comparison subroutine no longer causes a bus error if run multiple times. [perl #71076]
448 =head1 New or Changed Diagnostics
454 C<split> now warns when called in void context
459 C<printf>-style functions called with too few arguments will now issue the warning C<"Missing argument in %s"> [perl #71000]
466 Many modules updated from CPAN incorporate new tests.
470 =item t/comp/final_line_num.t
472 See if line numbers are correct at EOF
474 =item t/comp/form_scope.t
476 See if format scoping works
478 =item t/comp/line_debug.t
480 See if @{"_<$file"} works
482 =item t/op/filetest_t.t
484 See if -t file test works
490 =item t/op/utf8cache.t
492 Tests malfunctions of utf8 cache
494 =item t/re/uniprops.t
496 Test unicode \p{} regex constructs
502 The following items are now deprecated.
506 =item Use of "goto" to jump into a construct is deprecated
508 Using C<goto> to jump from an outer scope into an inner
509 scope is now deprecated. This rare use case was causing
510 problems in the implementation of scopes.
514 =head1 Acknowledgements
516 XXX The list of people to thank goes here.
519 =head1 Reporting Bugs
521 If you find what you think is a bug, you might check the articles
522 recently posted to the comp.lang.perl.misc newsgroup and the perl
523 bug database at http://rt.perl.org/perlbug/ . There may also be
524 information at http://www.perl.org/ , the Perl Home Page.
526 If you believe you have an unreported bug, please run the B<perlbug>
527 program included with your release. Be sure to trim your bug down
528 to a tiny but sufficient test case. Your bug report, along with the
529 output of C<perl -V>, will be sent off to perlbug@perl.org to be
530 analysed by the Perl porting team.
532 If the bug you are reporting has security implications, which make it
533 inappropriate to send to a publicly archived mailing list, then please send
534 it to perl5-security-report@perl.org. This points to a closed subscription
535 unarchived mailing list, which includes all the core committers, who be able
536 to help assess the impact of issues, figure out a resolution, and help
537 co-ordinate the release of patches to mitigate or fix the problem across all
538 platforms on which Perl is supported. Please only use this address for
539 security issues in the Perl core, not for modules independently
544 The F<Changes> file for an explanation of how to view exhaustive details
547 The F<INSTALL> file for how to build Perl.
549 The F<README> file for general stuff.
551 The F<Artistic> and F<Copying> files for copyright information.