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 The generated files in the C<lib/unicore/To> directory are now more
155 clearly marked as being stable, directly usable by applications.
156 New hash entries in them give the format of the normal entries,
157 which allows for easier machine parsing. Perl can generate files
158 in this directory for any property, though most are suppressed. An
159 installation can choose to change which get written. Instructions
160 are in L<perluniprops>.
162 =head2 Regular Expressions
164 U+0FFFF is now a legal character in regular expressions.
166 =head1 Modules and Pragmata
168 =head2 Pragmata Changes
174 Upgraded from version 1.19 to 1.20.
178 This pragma no longer suppresses C<Use of uninitialized value in range (or flip)> warnings. [perl #71204]
182 Upgraded from 1.13 to 1.14. Added the C<unicode_strings> feature:
184 use feature "unicode_strings";
186 This pragma turns on Unicode semantics for the case-changing operations
187 (uc/lc/ucfirst/lcfirst) on strings that don't have the internal UTF-8 flag set,
188 but that contain single-byte characters between 128 and 255.
192 The experimental C<legacy> pragma, introduced in 5.11.2, has been removed,
193 and its functionality replaced by the new feature pragma, C<use feature
198 Upgraded from version 1.74 to 1.75.
202 Upgraded from 1.07 to 1.08. Added new C<warnings::fatal_enabled()> function.
206 =head2 Updated Modules
210 =item C<Archive::Extract>
212 Upgraded from version 0.34 to 0.36.
216 Upgraded from version 1.94_51 to 1.94_53. Includes better bzip2 support,
217 improved FirstTime experience with auto-selection of CPAN mirrors, proper
218 handling of modules removed from the Perl core, and an updated 'cpan'
223 Upgraded from version 0.89_09 to 0.90.
227 Upgraded from version 2.38 to 2.39.
229 =item C<ExtUtils::MakeMaker>
231 Upgraded from version 6.55_02 to 6.56. Adds new BUILD_REQUIRES key to
232 indicate build-only prerequisites. Also adds support for
233 mingw64 and the new "package NAME VERSION" syntax.
237 Upgraded from version 2.08 to 2.08_01.
239 =item C<Module::Build>
241 Upgraded from version 0.35_09 to 0.36. Compared to 0.35, this version has a
242 new 'installdeps' action, supports the PERL_MB_OPT environment variable, adds a
243 'share_dir' property for L<File::ShareDir> support, support the "package NAME
244 VERSION" syntax and has many other enhancements and bug fixes. The
245 'passthrough' style of Module::Build::Compat has been deprecated.
247 =item C<Module::CoreList>
249 Upgraded from version 2.23 to 2.24.
253 Upgraded from version 1.18 to 1.19. Error codes for C<getaddrinfo()> and C<getnameinfo()> are now
258 Upgraded from version 3.10 to 3.13.
262 Upgraded from version 2.19 to 2.20.
266 =head1 Utility Changes
272 No longer reports "Message sent" when it hasn't actually sent the message
276 =head1 Changes to Existing Documentation
278 The Pod specification (L<perlpodspec>) has been updated to bring the
279 specification in line with modern usage already supported by most Pod systems.
280 A parameter string may now follow the format name in a "begin/end" region.
281 Links to URIs with a text description are now allowed. The usage of
282 C<LE<lt>"section"E<gt>> has been marked as deprecated.
284 L<if.pm|if> has been documented in L<perlfunc/use> as a means to get
285 conditional loading of modules despite the implicit BEGIN block around C<use>.
289 =head1 Installation and Configuration Improvements
291 =head2 Testing improvements
295 =item It's now possible to override C<PERL5OPT> and friends in F<t/TEST>
299 =head2 Platform Specific Changes
309 Always add a manifest resource to C<perl.exe> to specify the <trustInfo>
310 settings for Windows Vista and later. Without this setting Windows
311 will treat C<perl.exe> as a legacy application and apply various
312 heuristics like redirecting access to protected file system areas
313 (like the "Program Files" folder) to the users "VirtualStore"
314 instead of generating a proper "permission denied" error.
316 For VC8 and VC9 this manifest setting is automatically generated by
317 the compiler/linker (together with the binding information for their
318 respective runtime libraries); for all other compilers we need to
319 embed the manifest resource explicitly in the external resource file.
321 This change also requests the Microsoft Common-Controls version 6.0
322 (themed controls introduced in Windows XP) via the dependency list
323 in the assembly manifest. For VC8 and VC9 this is specified using the
324 C</manifestdependency> linker commandline option instead.
332 =item Enable IPv6 support on cygwin 1.7 and newer
340 =item Make -UDEBUGGING the default on VMS for 5.12.0.
342 Like it has been everywhere else for ages and ages. Also make
343 command-line selection of -UDEBUGGING and -DDEBUGGING work in
344 configure.com; before the only way to turn it off was by saying
345 no in answer to the interactive question.
351 =head1 Selected Bug Fixes
357 Ensure that pp_qr returns a new regexp SV each time. Resolves RT #69852.
359 Instead of returning a(nother) reference to the (pre-compiled) regexp in the
360 optree, use reg_temp_copy() to create a copy of it, and return a reference to
361 that. This resolves issues about Regexp::DESTROY not being called in a timely
362 fashion (the original bug tracked by RT #69852), as well as bugs related to
363 blessing regexps, and of assigning to regexps, as described in correspondence
366 It transpires that we also need to undo the SvPVX() sharing when ithreads
367 cloning a Regexp SV, because mother_re is set to NULL, instead of a cloned
368 copy of the mother_re. This change might fix bugs with regexps and threads in
369 certain other situations, but as yet neither tests nor bug reports have
370 indicated any problems, so it might not actually be an edge case that it's
375 Several compilation errors and segfaults when perl was built with C<-Dmad> were fixed.
379 Fixes for lexer API changes in 5.11.2 which broke NYTProf's savesrc option.
383 F<-t> should only return TRUE for file handles connected to a TTY
385 The Microsoft C version of isatty() returns TRUE for all
386 character mode devices, including the /dev/null style "nul"
387 device and printers like "lpt1".
391 Fixed a regression caused by commit fafafbaf which caused a panic during parameter passing [perl #70171]
396 On systems which in-place edits without backup files, -i'*' now works as the documentation says it does [perl #70802]
400 Saving and restoring magic flags no longer loses readonly flag.
404 The malformed syntax C<grep EXPR LIST> (note the missing comma) no longer
405 causes abrupt and total failure.
409 Regular expressions compiled with C<qr{}> literals properly set C<$'> when
414 Using named subroutines with C<sort> should no longer lead to bus errors [perl
419 Numerous bugfixes catch small issues caused by the recently-added Lexer API.
423 Smart match against C<@_> sometimes gave false negatives negatives. [perl #71078]
427 C<$@> may now be assigned a read-only value (without error or busting the stack).
431 C<sort> called recursively from within an active comparison subroutine no longer causes a bus error if run multiple times. [perl #71076]
435 =head1 New or Changed Diagnostics
441 C<split> now warns when called in void context
446 C<printf>-style functions called with too few arguments will now issue the warning C<"Missing argument in %s"> [perl #71000]
453 Many modules updated from CPAN incorporate new tests.
457 =item t/comp/final_line_num.t
459 See if line numbers are correct at EOF
461 =item t/comp/form_scope.t
463 See if format scoping works
465 =item t/comp/line_debug.t
467 See if @{"_<$file"} works
469 =item t/op/filetest_t.t
471 See if -t file test works
477 =item t/op/utf8cache.t
479 Tests malfunctions of utf8 cache
481 =item t/re/uniprops.t
483 Test unicode \p{} regex constructs
489 The following items are now deprecated.
493 =item Use of "goto" to jump into a construct is deprecated
495 Using C<goto> to jump from an outer scope into an inner
496 scope is now deprecated. This rare use case was causing
497 problems in the implementation of scopes.
501 =head1 Acknowledgements
503 Perl 5.11.3 represents approximately one month of development since
504 Perl 5.11.2 and contains 61407 lines of changes across 396 files
505 from 40 authors and committers:
507 Abigail, Alex Davies, Alexandr Ciornii, Andrew Rodland, Andy
508 Dougherty, Bram, brian d foy, Chip Salzenberg, Chris Williams, Craig
509 A. Berry, Daniel Frederick Crisman, David Golden, Dennis Kaarsemaker,
510 Eric Brine, Father Chrysostomos, Gene Sullivan, Gerard Goossen, H.
511 Merijn Brand, Hugo van der Sanden, Jan Dubois, Jerry D. Hedden,
512 Jesse Vincent, Jim Cromie, Karl Williamson, Leon Brocard, Max
513 Maischein, Michael Breen, Moritz Lenz, Nicholas Clark, Rafael
514 Garcia-Suarez, Reini Urban, Ricardo Signes, Stepan Kasal, Steve
515 Hay, Steve Peters, Tim Bunce, Tony Cook, Vincent Pit and Zefram.
517 Many of the changes included in this version originated in the CPAN
518 modules included in Perl's core. We're grateful to the entire CPAN
519 community for helping Perl to flourish.
521 =head1 Reporting Bugs
523 If you find what you think is a bug, you might check the articles
524 recently posted to the comp.lang.perl.misc newsgroup and the perl
525 bug database at http://rt.perl.org/perlbug/ . There may also be
526 information at http://www.perl.org/ , the Perl Home Page.
528 If you believe you have an unreported bug, please run the B<perlbug>
529 program included with your release. Be sure to trim your bug down
530 to a tiny but sufficient test case. Your bug report, along with the
531 output of C<perl -V>, will be sent off to perlbug@perl.org to be
532 analysed by the Perl porting team.
534 If the bug you are reporting has security implications, which make it
535 inappropriate to send to a publicly archived mailing list, then please send
536 it to perl5-security-report@perl.org. This points to a closed subscription
537 unarchived mailing list, which includes all the core committers, who be able
538 to help assess the impact of issues, figure out a resolution, and help
539 co-ordinate the release of patches to mitigate or fix the problem across all
540 platforms on which Perl is supported. Please only use this address for
541 security issues in the Perl core, not for modules independently
546 The F<Changes> file for an explanation of how to view exhaustive details
549 The F<INSTALL> file for how to build Perl.
551 The F<README> file for general stuff.
553 The F<Artistic> and F<Copying> files for copyright information.