diff options
Diffstat (limited to 'pod/perl593delta.pod')
| -rw-r--r-- | pod/perl593delta.pod | 171 |
1 files changed, 147 insertions, 24 deletions
diff --git a/pod/perl593delta.pod b/pod/perl593delta.pod index 2262c40615..2af1af6305 100644 --- a/pod/perl593delta.pod +++ b/pod/perl593delta.pod @@ -12,8 +12,9 @@ L<perl592delta> for the differences between 5.8.0 and 5.9.2. =head2 Parsing of C<-f _> -C<_> is now forced to be a bareword after a filetest operator. This solves -a number of misparsing issues when a global C<_> subroutine is defined. +The identifier C<_> is now forced to be a bareword after a filetest +operator. This solves a number of misparsing issues when a global C<_> +subroutine is defined. =head2 C<mkdir()> @@ -43,7 +44,7 @@ The C<sort> pragma is now lexically scoped. Its effect used to be global. =head2 The C<feature> pragma The C<feature> pragma is used to enable new syntax that would break Perl's -backward-compatibility with older releases of the language. It's a lexical +backwards-compatibility with older releases of the language. It's a lexical pragma, like C<strict> or C<warnings>. Currently the following new features are available: C<switch> (adds a @@ -52,12 +53,33 @@ switch statement), C<~~> (adds a Perl 6-like smart match operator), C<say> Those features are described below. Note that C<err> low-precedence defined-or operator used to be enabled by -default, but as a weak keyword. It's now only recognized when explicitly -turned on. +default (although as a weak keyword, meaning that any function would +override it). It's now only recognized when explicitly turned on (and is +then a regular keyword). + +Those features, and the C<feature> pragma itself, have been contributed by +Robin Houston. =head2 Switch and Smart Match operator -XXX +Perl 5 now has a switch statement. It's available when C<use feature +'switch'> is in effect. This feature introduces three new keywords, +C<given>, C<when>, and C<default> : + + given ($foo) { + when (/^abc/) { $abc = 1; } + when (/^def/) { $def = 1; } + when (/^xyz/) { $xyz = 1; } + default { $nothing = 1; } + } + +A more complete description of how Perl matches the switch variable +against the C<when> conditions is given in L<perlsyn/"Switch statements">. + +This kind of match is called I<smart match>, and it's also possible to use +it outside of switch statements, via the new C<~~> operator (enabled via +the C<use feature '~~'> directive). See L<perlsyn/"Smart matching in +detail">. =head2 C<say()> @@ -71,21 +93,21 @@ Perl has now support for the C<CLONE_SKIP> special subroutine. Like C<CLONE>, C<CLONE_SKIP> is called once per package; however, it is called just before cloning starts, and in the context of the parent thread. If it returns a true value, then no objects of that class will be cloned. See -L<perlmod> for details. +L<perlmod> for details. (Contributed by Dave Mitchell.) =head2 C<${^CHILD_ERROR_NATIVE}> A new internal variable, C<${^CHILD_ERROR_NATIVE}>, gives the native status returned by the last pipe close, backtick command, successful call to wait() or waitpid(), or from the system() operator. See L<perlrun> for -details. +details. (Contributed by Gisle Aas.) =head2 Assertions The support for assertions, introduced in perl 5.9.0, has been improved. The syntax for the C<-A> command-line switch has changed; it now accepts an optional module name, defaulting to C<assertions::activate>. See -L<assertions> and L<perlrun>. +L<assertions> and L<perlrun>. (Contributed by Salvador Fandiño García.) =head2 Unicode Character Database 4.1.0 @@ -113,7 +135,7 @@ into eval(""). =head2 New B<-E> command-line switch B<-E> is equivalent to B<-e>, but it implicitly enables all -optional features. +optional features (like C<use feature ":5.10">). =head2 C<chdir>, C<chmod> and C<chown> on filehandles @@ -121,33 +143,87 @@ C<chdir>, C<chmod> and C<chown> can now work on filehandles as well as filenames, if the system supports respectively C<fchdir>, C<fchmod> and C<fchown>, thanks to a patch provided by Gisle Aas. +=head2 OS groups + +C<$(> and C<$)> now return groups in the order where the OS returns them, +thanks to Gisle Aas. This wasn't previously the case. + =head1 Modules and Pragmata -=head2 C<feature> +=head2 New Core Modules + +=over 4 + +=item * + +A new pragma, C<feature>, has been added; see above in L</"Core +Enhancements">. + +=item * + +C<assertions::compat>, also available on CPAN, allows to use assertions on +perl versions prior to 5.9.0 (that is the first one to natively support +them). + +=item * + +C<Math::BigInt::FastCalc> is an XS-enabled, and thus faster, version of +C<Math::BigInt::Calc>. + +=item * + +C<Compress::Zlib> is an interface to the zlib compression library. It +comes with a bundled version of zlib, so having a working zlib is not a +prerequisite to install it. It's used by C<Archive::Tar> (see below). + +=item * -This new module implements the C<feature> pragma; see above in -L</"Core Enhancements">. +C<IO::Zlib> is an C<IO::>-style interface to C<Compress::Zlib>. -=head2 C<assertions::compat> +=item * -=head2 C<Math::BigInt::FastCalc> +C<Archive::Tar> is a module to manipulate C<tar> archives. -=head2 C<Compress::Zlib> +=item * -=head2 C<IO::Zlib> +C<Digest::SHA> is a module used to calculate many types of SHA digests, +has been included for SHA support in the CPAN module. -=head2 C<Archive::Tar> +=back =head1 Utility Changes =head2 C<ptar> +C<ptar> is a pure perl implementation of C<tar>, that comes with +C<Archive::Tar>. + +=head2 C<shasum> + +This command-line utility, used to print or to check SHA digests, comes +with the new C<Digest::SHA> module. + +=head2 C<h2xs> enhancements + +C<h2xs> implements new option C<--use-xsloader> to force use of +C<XSLoader> even in backwards compatible modules. + +The handling of authors' names that had apostrophes has been fixed. + +Any enums with negative values are now skipped. + +=head2 C<perlivp> enhancements + +C<perlivp> implements new option C<-a> and will not check for F<*.ph> +files by default any more. Use the C<-a> option to run I<all> tests. + =head1 Documentation =head2 Perl Glossary The L<perlglossary> manpage is a glossary of terms used in the Perl -documentation, technical and otherwise. +documentation, technical and otherwise, kindly provided by O'Reilly Media, +inc. =head1 Performance Enhancements @@ -156,7 +232,7 @@ documentation, technical and otherwise. Some pure-perl code that perl was using to retrieve Unicode properties and transliteration mappings has been reimplemented in XS. -=head2 Constants subroutines +=head2 Constant subroutines XXX @@ -180,6 +256,18 @@ and to speed up some cases. =head1 Installation and Configuration Improvements +=head2 Compilation improvements + +Parallel makes should work properly now, although there may still be problems +if C<make test> is instructed to run in parallel. + +Building with Borland's compilers on Win32 should work more smoothly. In +particular Steve Hay has worked to side step many warnings emitted by their +compilers and at least one C compiler internal error. + +Perl extensions on Windows now can be statically built into the Perl DLL, +thanks to a work by Vadim Konovalov. + =head2 New Or Improved Platforms Perl is being ported to Symbian OS. See L<perlsymbian> for more @@ -194,7 +282,10 @@ improved (Borland C++, Visual C++ 7.0). =head2 New probes -Perl will detect and use internally futimes(2) if available. +C<Configure> will now detect C<clearenv> and C<unsetenv>, thanks to a +patch from Alan Burlison. It will also probe for C<futimes> (and use it +internally if available), and whether C<sprintf> correctly returns the +length of the formatted string. =head2 Module auxiliary files @@ -244,8 +335,17 @@ Using the sprintf() function with some formats could lead to a buffer overflow in some specific cases. This has been fixed, along with several other bugs, notably in bound checking. -In related fixes, a format string injection vulnerability has been fixed -in Sys::Syslog. +In related fixes, it was possible for badly written code that did not follow +the documentation of C<Sys::Syslog> to have formatting vulnerabilities. +C<Sys::Syslog> has been changed to protect people from poor quality third +party code. + +=head2 no warnings 'category' works correctly with -w + +Previously when running with warnings enabled globally via C<-w>, selective +disabling of specific warning categories would actually turn off all warnings. +This is now fixed; now C<no warnings 'io';> will only turn off warnings in the +C<io> class. Previously it would erroneously turn off all warnings. =head2 Smaller fixes @@ -332,6 +432,20 @@ This is a new warning, produced in situations like the following one: $r = do {my @a; \$#a}; $$r = 503; +=head2 Non-string passed as bitmask + +This is a new warning, produced when number has been passed as a argument to +select(), instead of a bitmask. + + # Wrong, will now warn + $rin = fileno(STDIN); + ($nfound,$timeleft) = select($rout=$rin, undef, undef, $timeout); + + # Should be + $rin = ''; + vec($rin,fileno(STDIN),1) = 1; + ($nfound,$timeleft) = select($rout=$rin, undef, undef, $timeout); + =head2 Search pattern not terminated or ternary operator parsed as search pattern This syntax error indicates that the lexer couldn't find the final @@ -360,7 +474,16 @@ either closed or not really a dirhandle. =head1 Changed Internals -XXX consting +In general, the source code of perl has been refactored, tied up, and +optimized in many places. Also, memory management and allocation has been +improved in a couple of points. + +Andy Lester supplied many improvements to determine which function +parameters and local variables could actually be declared C<const> to the C +compiler. Steve Peters provided new C<*_set> macros and reworked the core to +use these rather than assigning to macros in LVALUE context. + +Dave Mitchell improved the lexer debugging output under C<-DT>. A new file, F<mathoms.c>, has been added. It contains functions that are no longer used in the perl core, but that remain available for binary or |