| 1 | =encoding utf8 |
| 2 | |
| 3 | =head1 NAME |
| 4 | |
| 5 | perl5195delta - what is new for perl v5.19.5 |
| 6 | |
| 7 | =head1 DESCRIPTION |
| 8 | |
| 9 | This document describes differences between the 5.19.4 release and the 5.19.5 |
| 10 | release. |
| 11 | |
| 12 | If you are upgrading from an earlier release such as 5.19.3, first read |
| 13 | L<perl5194delta>, which describes differences between 5.19.3 and 5.19.4. |
| 14 | |
| 15 | =head1 Core Enhancements |
| 16 | |
| 17 | =head2 Unicode 6.3 now supported |
| 18 | |
| 19 | Perl now supports and is shipped with Unicode 6.3 (though Perl may be |
| 20 | recompiled with any previous Unicode release as well). A detailed list of |
| 21 | Unicode 6.3 changes is at L<http://www.unicode.org/versions/Unicode6.3.0/>. |
| 22 | |
| 23 | =head2 Experimental Postfix Dereferencing |
| 24 | |
| 25 | When the C<postderef> feature is in effect, the following syntactical |
| 26 | equivalencies are set up: |
| 27 | |
| 28 | $sref->$*; # same as ${ $sref } # interpolates |
| 29 | $aref->@*; # same as @{ $aref } # interpolates |
| 30 | $href->%*; # same as %{ $href } |
| 31 | $cref->&*; # same as &{ $cref } |
| 32 | $gref->**; # same as *{ $gref } |
| 33 | |
| 34 | $gref->*{ $slot }; # same as *{ $gref }{ $slot } |
| 35 | |
| 36 | $aref->@[ ... ]; # same as @$aref[ ... ] # interpolates |
| 37 | $href->@{ ... }; # same as @$href{ ... } # interpolates |
| 38 | $aref->%[ ... ]; # same as %$aref[ ... ] |
| 39 | $href->%{ ... }; # same as %$href{ ... } |
| 40 | |
| 41 | Those marked as interpolating only interpolate if the associated |
| 42 | C<postderef_qq> feature is also enabled. This feature is B<experimental> and |
| 43 | will trigger C<experimental::postderef>-category warnings when used, unless |
| 44 | they are suppressed. |
| 45 | |
| 46 | For more information, consult L<the Postfix Dereference Syntax section of |
| 47 | perlref|perlref/Postfix Dereference Syntax>. |
| 48 | |
| 49 | =head2 C<sub>s now take a C<prototype> attribute |
| 50 | |
| 51 | When declaring or defining a C<sub>, the prototype can now be specified inside |
| 52 | of a C<prototype> attribute instead of in parens following the name. |
| 53 | |
| 54 | For example, C<sub foo($$){}> could be rewritten as |
| 55 | C<sub foo : prototype($$){}>. |
| 56 | |
| 57 | =head1 Incompatible Changes |
| 58 | |
| 59 | =head2 Functions C<PerlIO_vsprintf> and C<PerlIO_sprintf> have been removed |
| 60 | |
| 61 | These two functions, undocumented, unused in CPAN, and problematic, have been |
| 62 | removed. |
| 63 | |
| 64 | =head1 Performance Enhancements |
| 65 | |
| 66 | =over 4 |
| 67 | |
| 68 | =item * |
| 69 | |
| 70 | Perl has an optimizer for regular expression patterns. It analyzes the pattern |
| 71 | to find things such as the minimum length a string has to be to match, etc. It |
| 72 | now better handles code points that are above the Latin1 range. |
| 73 | |
| 74 | =back |
| 75 | |
| 76 | =head1 Modules and Pragmata |
| 77 | |
| 78 | =head2 Updated Modules and Pragmata |
| 79 | |
| 80 | =over 4 |
| 81 | |
| 82 | =item * |
| 83 | |
| 84 | L<attributes> has been upgraded from version 0.21 to 0.22. |
| 85 | |
| 86 | Support has been added for the C<prototype> attribute. |
| 87 | |
| 88 | =item * |
| 89 | |
| 90 | L<autodie> has been upgraded from version 2.21 to 2.22. |
| 91 | |
| 92 | No changes have been made to the installed code other than the version bump to |
| 93 | keep in sync with the latest CPAN release. |
| 94 | |
| 95 | =item * |
| 96 | |
| 97 | L<CPAN::Meta> has been upgraded from version 2.132620 to 2.132830. |
| 98 | |
| 99 | L<CPAN::Meta::Prereqs> now has a C<merged_requirements> method for combining |
| 100 | requirements across multiple phases and types, and an invalid 'meta-spec' is no |
| 101 | longer a fatal error. |
| 102 | |
| 103 | =item * |
| 104 | |
| 105 | L<CPAN::Meta::Requirements> has been upgraded from version 2.123 to 2.125. |
| 106 | |
| 107 | No changes have been made to the installed code other than the version bump to |
| 108 | keep in sync with the latest CPAN release. |
| 109 | |
| 110 | =item * |
| 111 | |
| 112 | L<CPAN::Meta::YAML> has been upgraded from version 0.008 to 0.010. |
| 113 | |
| 114 | No material changes have been made to the installed code other than the version |
| 115 | bump to keep in sync with the latest CPAN release. |
| 116 | |
| 117 | =item * |
| 118 | |
| 119 | L<Cwd> has been upgraded from version 3.44 to 3.45. |
| 120 | |
| 121 | An obsolete #define has been removed from the XS code. |
| 122 | |
| 123 | =item * |
| 124 | |
| 125 | L<ExtUtils::Install> has been upgraded from version 1.60 to 1.61. |
| 126 | |
| 127 | Some POD formatting errors in the documentation have been corrected. |
| 128 | |
| 129 | =item * |
| 130 | |
| 131 | L<ExtUtils::MakeMaker> has been upgraded from version 6.76 to 6.80. |
| 132 | |
| 133 | Numerous updates and bug fixes are incorporated. See the F<Changes> file in |
| 134 | the CPAN distribution for full details. |
| 135 | |
| 136 | =item * |
| 137 | |
| 138 | L<feature> has been upgraded from version 1.33 to 1.34. |
| 139 | |
| 140 | The new features C<postderef> and C<postderef_qq> have been added. |
| 141 | |
| 142 | =item * |
| 143 | |
| 144 | L<File::Fetch> has been upgraded from version 0.42 to 0.44. |
| 145 | |
| 146 | No changes have been made to the installed code other than the version bump to |
| 147 | keep in sync with the latest CPAN release. |
| 148 | |
| 149 | =item * |
| 150 | |
| 151 | L<File::Glob> has been upgraded from version 1.21 to 1.22. |
| 152 | |
| 153 | Since Perl 5.16, code that used C<glob> inside a thread had been |
| 154 | unintentionally sharing state between threads. This has now been fixed. [perl |
| 155 | #119897/#117823] |
| 156 | |
| 157 | =item * |
| 158 | |
| 159 | L<File::Temp> has been upgraded from version 0.2301 to 0.2304. |
| 160 | |
| 161 | Required versions of other modules used are now listed more explicitly, L<base> |
| 162 | is now used instead of L<parent>, and L<Exporter> is no longer inherited from. |
| 163 | |
| 164 | =item * |
| 165 | |
| 166 | L<Getopt::Long> has been upgraded from version 2.41 to 2.42. |
| 167 | |
| 168 | The floating point specifier C<name=f> no longer erroneously accepts values |
| 169 | like 1.2.3. [cpan #88707] |
| 170 | |
| 171 | =item * |
| 172 | |
| 173 | L<HTTP::Tiny> has been upgraded from version 0.035 to 0.036. |
| 174 | |
| 175 | No changes have been made to the installed code other than the version bump to |
| 176 | keep in sync with the latest CPAN release. |
| 177 | |
| 178 | =item * |
| 179 | |
| 180 | L<IPC::Cmd> has been upgraded from version 0.84 to 0.84_01. |
| 181 | |
| 182 | No changes have been made to the installed code, but a test script has been |
| 183 | fixed for Solaris (and potentially other SVR* variants). |
| 184 | |
| 185 | =item * |
| 186 | |
| 187 | L<JSON::PP> has been upgraded from version 2.27202_01 to 2.27203. |
| 188 | |
| 189 | A return/or precedence issue in C<_incr_parse> has been fixed. |
| 190 | |
| 191 | =item * |
| 192 | |
| 193 | L<List::Util> has been upgraded from version 1.32 to 1.35. |
| 194 | |
| 195 | The list functions C<any>, C<all>, C<none>, C<notall> and C<product> have been |
| 196 | added, and C<reduce> and C<first> are now implemented even in the absence of |
| 197 | MULTICALL. |
| 198 | |
| 199 | =item * |
| 200 | |
| 201 | L<Module::CoreList> has been upgraded from version 2.99 to 3.00. |
| 202 | |
| 203 | The list of Perl versions covered has been updated, %delta is now exported, and |
| 204 | a bug in C<is_core> whereby it wrongly assumed a linear list of releases has |
| 205 | been fixed. |
| 206 | |
| 207 | =item * |
| 208 | |
| 209 | L<Module::Metadata> has been upgraded from version 1.000018 to 1.000019. |
| 210 | |
| 211 | Warnings are now disabled during version evaluation. |
| 212 | |
| 213 | =item * |
| 214 | |
| 215 | L<Parse::CPAN::Meta> has been upgraded from version 1.4407 to 1.4409. |
| 216 | |
| 217 | No changes have been made to the installed code other than the version bump to |
| 218 | keep in sync with the latest CPAN release. |
| 219 | |
| 220 | =item * |
| 221 | |
| 222 | L<Perl::OSType> has been upgraded from version 1.005 to 1.006. |
| 223 | |
| 224 | No changes have been made to the installed code other than the version bump to |
| 225 | keep in sync with the latest CPAN release. |
| 226 | |
| 227 | =item * |
| 228 | |
| 229 | L<PerlIO::scalar> has been upgraded from version 0.16 to 0.17. |
| 230 | |
| 231 | An infinite loop when reading from a filehandle opened from a reference has |
| 232 | been fixed by first stringifying the reference. [perl #119529] |
| 233 | |
| 234 | =item * |
| 235 | |
| 236 | The podlators modules have been upgraded from version 2.5.1 to 2.5.3. |
| 237 | |
| 238 | Numerous updates and bug fixes are incorporated. See the F<Changes> file in |
| 239 | the CPAN distribution for full details. |
| 240 | |
| 241 | =item * |
| 242 | |
| 243 | L<Test::Harness> has been upgraded from version 3.28 to 3.29. |
| 244 | |
| 245 | All modules now use C<our> rather than C<use vars>, have C<use warnings> |
| 246 | enabled and C<use parent> instead of @ISA. |
| 247 | |
| 248 | =item * |
| 249 | |
| 250 | L<Test::Simple> has been upgraded from version 0.98_06 to 0.99. |
| 251 | |
| 252 | Numerous updates and bug fixes are incorporated. See the F<Changes> file in |
| 253 | the CPAN distribution for full details. |
| 254 | |
| 255 | =item * |
| 256 | |
| 257 | L<threads> has been upgraded from version 1.87 to 1.89. |
| 258 | |
| 259 | The documentation of C<alarm> and C<_handle> has been updated. |
| 260 | |
| 261 | =item * |
| 262 | |
| 263 | L<Unicode::Normalize> has been upgraded from version 1.16 to 1.17. |
| 264 | |
| 265 | The module now C<die>s if it cannot get Unicode code points using C<unpack>. |
| 266 | (There is already a similar C<die> if Unicode code points cannot be stringified |
| 267 | using C<pack>.) |
| 268 | |
| 269 | =item * |
| 270 | |
| 271 | L<Unicode::UCD> has been upgraded from version 0.54 to 0.55. |
| 272 | |
| 273 | An internals-only change has been made to handle changes in format within some |
| 274 | character database tables. |
| 275 | |
| 276 | =item * |
| 277 | |
| 278 | L<warnings> has been upgraded from version 1.19 to 1.20. |
| 279 | |
| 280 | The new warnings category C<experimental::postderef> has been added. |
| 281 | |
| 282 | =back |
| 283 | |
| 284 | =head1 Documentation |
| 285 | |
| 286 | =head2 Changes to Existing Documentation |
| 287 | |
| 288 | =head3 L<perlref> |
| 289 | |
| 290 | =over 4 |
| 291 | |
| 292 | =item * |
| 293 | |
| 294 | Documentation of the new postfix dereference syntax has been added. |
| 295 | |
| 296 | =back |
| 297 | |
| 298 | =head3 L<perlreguts> |
| 299 | |
| 300 | =over 4 |
| 301 | |
| 302 | =item * |
| 303 | |
| 304 | The documentation has been updated in the light of recent changes to |
| 305 | F<regcomp.c>. |
| 306 | |
| 307 | =back |
| 308 | |
| 309 | =head3 L<perlvar> |
| 310 | |
| 311 | =over 4 |
| 312 | |
| 313 | =item * |
| 314 | |
| 315 | Three L<English> variable names which have long been documented but do not |
| 316 | actually exist have been removed from the documentation. |
| 317 | |
| 318 | =back |
| 319 | |
| 320 | =head1 Diagnostics |
| 321 | |
| 322 | The following additions or changes have been made to diagnostic output, |
| 323 | including warnings and fatal error messages. For the complete list of |
| 324 | diagnostic messages, see L<perldiag>. |
| 325 | |
| 326 | =head2 New Diagnostics |
| 327 | |
| 328 | =head3 New Warnings |
| 329 | |
| 330 | =over 4 |
| 331 | |
| 332 | =item * |
| 333 | |
| 334 | L<Attribute prototype(%s) discards earlier prototype attribute in same sub|perldiag/"Attribute prototype(%s) discards earlier prototype attribute in same sub"> |
| 335 | |
| 336 | (W misc) A sub was declared as sub foo : prototype(A) : prototype(B) {}, for |
| 337 | example. Since each sub can only have one prototype, the earlier |
| 338 | declaration(s) are discarded while the last one is applied. |
| 339 | |
| 340 | =item * |
| 341 | |
| 342 | L<Postfix dereference is experimental|perldiag/"Postfix dereference is experimental"> |
| 343 | |
| 344 | (S experimental::postderef) This warning is emitted if you use the experimental |
| 345 | postfix dereference syntax. Simply suppress the warning if you want to use the |
| 346 | feature, but know that in doing so you are taking the risk of using an |
| 347 | experimental feature which may change or be removed in a future Perl version: |
| 348 | |
| 349 | no warnings "experimental::postderef"; |
| 350 | use feature "postderef", "postderef_qq"; |
| 351 | $ref->$*; |
| 352 | $aref->@*; |
| 353 | $aref->@[@indices]; |
| 354 | ... etc ... |
| 355 | |
| 356 | =item * |
| 357 | |
| 358 | L<Prototype '%s' overridden by attribute 'prototype(%s)' in %s|perldiag/"Prototype '%s' overridden by attribute 'prototype(%s)' in %s"> |
| 359 | |
| 360 | (W prototype) A prototype was declared in both the parentheses after the sub |
| 361 | name and via the prototype attribute. The prototype in parentheses is useless, |
| 362 | since it will be replaced by the prototype from the attribute before it's ever |
| 363 | used. |
| 364 | |
| 365 | =back |
| 366 | |
| 367 | =head1 Utility Changes |
| 368 | |
| 369 | =head3 L<a2p> |
| 370 | |
| 371 | =over 4 |
| 372 | |
| 373 | =item * |
| 374 | |
| 375 | A possible crash from an off-by-one error when trying to access before the |
| 376 | beginning of a buffer has been fixed. [perl #120244] |
| 377 | |
| 378 | =back |
| 379 | |
| 380 | =head1 Testing |
| 381 | |
| 382 | =over 4 |
| 383 | |
| 384 | =item * |
| 385 | |
| 386 | The new prototype attribute syntax is tested by a new test script, |
| 387 | F<t/op/attrproto.t>. |
| 388 | |
| 389 | =item * |
| 390 | |
| 391 | The new test script F<t/io/closepid.t> tests that C<close> on the original of a |
| 392 | popen handle dupped to a standard handle no longer blocks internally on |
| 393 | C<waitpid(0, ...)>. |
| 394 | |
| 395 | =item * |
| 396 | |
| 397 | The new postfix dereference syntax is tested by a new test script, |
| 398 | F<t/op/postfixderef.t>. |
| 399 | |
| 400 | =back |
| 401 | |
| 402 | =head1 Platform Support |
| 403 | |
| 404 | =head2 Platform-Specific Notes |
| 405 | |
| 406 | =over 4 |
| 407 | |
| 408 | =item Windows |
| 409 | |
| 410 | The Windows MinGW/gcc build was broken in Perl 5.19.4 for some recent versions |
| 411 | of gcc-4.8, including those from http://mingw-w64.sourceforge.net/ . This has |
| 412 | now been fixed. [perl #120236] |
| 413 | |
| 414 | =back |
| 415 | |
| 416 | =head1 Selected Bug Fixes |
| 417 | |
| 418 | =over 4 |
| 419 | |
| 420 | =item * |
| 421 | |
| 422 | C<last> no longer returns values that the same statement has accumulated so |
| 423 | far, fixing amongst other things the long-standing bug that C<push @a, last> |
| 424 | would try to return the @a, copying it like a scalar in the process and |
| 425 | resulting in the error, "Bizarre copy of ARRAY in last." [perl #3112] |
| 426 | |
| 427 | =item * |
| 428 | |
| 429 | An optimization in Perl 5.18 made incorrect assumptions causing a bad |
| 430 | interaction with the L<Devel::CallParser> CPAN module. This was partially |
| 431 | fixed in Perl 5.19.4, but the fix was not sufficient and another fault has now |
| 432 | been corrected. |
| 433 | |
| 434 | =item * |
| 435 | |
| 436 | In some cases, closing file handles opened to pipe to or from a process, which |
| 437 | had been duplicated into a standard handle, would call perl's internal waitpid |
| 438 | wrapper with a pid of zero. With the fix for [perl #85228] this zero pid was |
| 439 | passed to C<waitpid>, possibly blocking the process. This wait for process |
| 440 | zero no longer occurs. [perl #119893] |
| 441 | |
| 442 | =item * |
| 443 | |
| 444 | The code that parses regex backrefs (or ambiguous backref/octals) such as \123 |
| 445 | did a simple atoi(), which could wrap round to negative values on long digit |
| 446 | strings and cause segmentation faults. This has now been fixed. [perl |
| 447 | #119505] |
| 448 | |
| 449 | =item * |
| 450 | |
| 451 | C<select> used to ignore magic on the fourth (timeout) argument, leading to |
| 452 | effects such as C<select> blocking indefinitely rather than the expected sleep |
| 453 | time. This has now been fixed. [perl #120102] |
| 454 | |
| 455 | =item * |
| 456 | |
| 457 | The class name in C<for my class $foo> is now parsed correctly. In the case of |
| 458 | the second character of the class name being followed by a digit (e.g. 'a1b') |
| 459 | this used to give the error "Missing $ on loop variable". [perl #120112] |
| 460 | |
| 461 | =back |
| 462 | |
| 463 | =head1 Acknowledgements |
| 464 | |
| 465 | Perl 5.19.5 represents approximately 4 weeks of development since Perl 5.19.4 |
| 466 | and contains approximately 76,000 lines of changes across 710 files from 27 |
| 467 | authors. |
| 468 | |
| 469 | Perl continues to flourish into its third decade thanks to a vibrant community |
| 470 | of users and developers. The following people are known to have contributed the |
| 471 | improvements that became Perl 5.19.5: |
| 472 | |
| 473 | Andy Dougherty, Brian Fraser, Chris 'BinGOs' Williams, Craig A. Berry, Dagfinn |
| 474 | Ilmari Mannsåker, Daniel Dragan, David Golden, David Mitchell, David Nicol, |
| 475 | Dominic Hargreaves, Eric Brine, Father Chrysostomos, Gideon Israel Dsouza, Hio, |
| 476 | James E Keenan, Jerry D. Hedden, Jesse Luehrs, Karl Williamson, Matthew |
| 477 | Horsfall, Max Maischein, Neil Bowers, Nicholas Clark, Peter Martini, Philip |
| 478 | Guenther, Ricardo Signes, Steve Hay, Tony Cook. |
| 479 | |
| 480 | The list above is almost certainly incomplete as it is automatically generated |
| 481 | from version control history. In particular, it does not include the names of |
| 482 | the (very much appreciated) contributors who reported issues to the Perl bug |
| 483 | tracker. |
| 484 | |
| 485 | Many of the changes included in this version originated in the CPAN modules |
| 486 | included in Perl's core. We're grateful to the entire CPAN community for |
| 487 | helping Perl to flourish. |
| 488 | |
| 489 | For a more complete list of all of Perl's historical contributors, please see |
| 490 | the F<AUTHORS> file in the Perl source distribution. |
| 491 | |
| 492 | =head1 Reporting Bugs |
| 493 | |
| 494 | If you find what you think is a bug, you might check the articles recently |
| 495 | posted to the comp.lang.perl.misc newsgroup and the perl bug database at |
| 496 | http://rt.perl.org/perlbug/ . There may also be information at |
| 497 | http://www.perl.org/ , the Perl Home Page. |
| 498 | |
| 499 | If you believe you have an unreported bug, please run the L<perlbug> program |
| 500 | included with your release. Be sure to trim your bug down to a tiny but |
| 501 | sufficient test case. Your bug report, along with the output of C<perl -V>, |
| 502 | will be sent off to perlbug@perl.org to be analysed by the Perl porting team. |
| 503 | |
| 504 | If the bug you are reporting has security implications, which make it |
| 505 | inappropriate to send to a publicly archived mailing list, then please send it |
| 506 | to perl5-security-report@perl.org. This points to a closed subscription |
| 507 | unarchived mailing list, which includes all the core committers, who will be |
| 508 | able to help assess the impact of issues, figure out a resolution, and help |
| 509 | co-ordinate the release of patches to mitigate or fix the problem across all |
| 510 | platforms on which Perl is supported. Please only use this address for |
| 511 | security issues in the Perl core, not for modules independently distributed on |
| 512 | CPAN. |
| 513 | |
| 514 | =head1 SEE ALSO |
| 515 | |
| 516 | The F<Changes> file for an explanation of how to view exhaustive details on |
| 517 | what changed. |
| 518 | |
| 519 | The F<INSTALL> file for how to build Perl. |
| 520 | |
| 521 | The F<README> file for general stuff. |
| 522 | |
| 523 | The F<Artistic> and F<Copying> files for copyright information. |
| 524 | |
| 525 | =cut |