=encoding utf8
-=for comment
-This has been completed up to 7e482323f, except for:
-8629c11317 smueller Escape double-quotes in generated #line directives
-8dc67a69b shlomif perl -d: display lines inside subroutines.
-3dfd1b5cd2 leont Export PerlIOBase_open
-
=head1 NAME
[ this is a template for a new perldelta file. Any text flagged as
XXX needs to be processed before release. ]
-perldelta - what is new for perl v5.15.7
+perldelta - what is new for perl v5.15.8
=head1 DESCRIPTION
-This document describes differences between the 5.15.6 release and
-the 5.15.7 release.
+This document describes differences between the 5.15.7 release and
+the 5.15.8 release.
-If you are upgrading from an earlier release such as 5.15.5, first read
-L<perl5156delta>, which describes differences between 5.15.5 and
-5.15.6.
+If you are upgrading from an earlier release such as 5.15.6, first read
+L<perl5157delta>, which describes differences between 5.15.6 and
+5.15.7.
=head1 Notice
[ List each enhancement as a =head2 entry ]
-=head2 C<use charnames> no longer needed for C<\N{I<name>}>
-
-The C<charnames> module is now automatically loaded when needed as if
-the C<:full> and C<:short> options had been specified. See
-L<charnames>.
-
-=head2 Improved performance for Unicode properties in regular expressions
-
-Matching a code point against a Unicode property is now done via a
-binary search instead of linear. This means for example that the worst
-case for a 1000 item property is 10 probes instead of 1000. This
-inefficiency has been compensated for in the past by permanently storing
-in a hash the results of a given probe plus the results for the adjacent
-64 code points, under the theory that near-by code points are likely to
-be searched for. A separate hash was used for each mention of a Unicode
-property in each regular expression. Thus, C<qr/\p{foo}abc\p{foo}/>
-would generate two hashes. Any probes in one instance would be unknown
-to the other, and the hashes could expand separately to be quite large
-if the regular expression were used on many different widely-separated
-code points. This can lead to running out of memory in extreme cases.
-Now, however, there is just one hash shared by all instances of a given
-property. This means that if C<\p{foo}> is matched against "A" in one
-regular expression in a thread, the result will be known immediately to
-all regular expressions, and the relentless march of using up memory is
-slowed considerably.
+=head2 Improved ability to mix locales and Unicode, including UTF-8 locales
+
+An optional parameter has been added to C<use locale>
+
+ use locale ':not_characters';
+
+which tells Perl to use all but the C<LC_CTYPE> and C<LC_COLLATE>
+portions of the current locale. Instead, the character set is assumed
+to be Unicode. This allows locales and Unicode to be seamlessly mixed,
+including the increasingly frequent UTF-8 locales. When using this
+hybrid form of locales, the C<:locale> layer to the L<open> pragma can
+be used to interface with the file system, and there are CPAN modules
+available for ARGV and environment variable conversions.
+
+Full details are in L<perllocale>.
+
+>>>>>>> Add :not_characters parameter to 'use locale'
=head1 Security
[ List each deprecation as a =head2 entry ]
-=head2 Deprecated Modules
-
-=over
-
-=item L<Version::Requirements>
-
-Version::Requirements is now DEPRECATED, use CPAN::Meta::Requirements,
-which is a drop-in replacement. It will be deleted from perl.git blead
-in v5.17.0.
-
-=back
-
=head1 Performance Enhancements
XXX Changes which enhance performance without changing behaviour go here. There
=item *
-Version declarations with the C<use> keyword (e.g., C<use 5.012>) are now
-faster, as they enable features without loading F<feature.pm>.
-
-=item *
-
-C<local $_> is faster now, as it no longer iterates through magic that it
-is not going to copy anyway.
+XXX
=back
=item *
-L<B::Deparse> has been upgraded from version 1.10 to version 1.11.
-
-It now deparses C<open('random string')> correctly. It used to omit the
-quotation marks, which did not work if the string were not a valid
-identifier [perl #91416].
-
-A similar bug also affected hash and array elements such as
-C<< 'random string'->[0] >>, which would deparse as C<$random string[0]>.
-This has been fixed.
-
-Those same syntaxes used to drop the package name from variables beginning
-with a punctuation mark, as in C<< "foo::]"->{$key} >>. This, too, has
-been fixed.
-
-B::Deparse no longer hangs when deparsing a program with stash
-circularities, such as C<BEGIN { *Acme::Acme:: = *Acme:: }> [perl #91384].
-
-C</$s[1]/> used to be deparsed as C<$s[1]> if @s were a lexical variable
-[perl #81424]. Similarly, C</$#s/> would be deparsed as C<$#s> for both
-lexical and package variables. These has been fixed.
-
-The C</applaud> regular expression flags are no longer omitted.
-
-Feature hints are now deparsed with C<use feature> rather than C<%^H>
-assignments.
-
-A regression in 1.10 that caused C<ambient_pragmas> to disabled strict mode
-in obscure cases has been fixed.
-
-Strict mode is now fully deparsed, including subs and vars [perl #24027].
-
-The global variables C<$(>, C<$|> and C<$)> are now deparsed with braces
-(i.e., C<${(}>) in regular expressions [perl #86060].
-
-=item *
-
-L<CGI> has been upgraded from version 3.58 to version 3.59.
-
-We no longer read from STDIN when the Content-Length is not set, preventing
-requests with no Content-Length from freezing in some cases. This is consistent
-with the CGI RFC 3875, and is also consistent with CGI::Simple. However, the old
-behavior may have been expected by some command-line uses of CGI.pm.
-
-=item *
-
-L<CPAN::Meta> has been upgraded from version 2.112621 to version 2.113640.
-
-Version::Requirements has now been merged as CPAN::Meta::Requirements.
-
-=item *
-
-L<CPANPLUS> has been upgraded from version 0.9113 to version 0.9116.
-
-=item *
-
-L<Data::Dumper> has been upgraded from version 2.135_01 to version
-2.135_03.
-
-It can now dump vstrings [perl #101162].
-
-The nameless typeglob (C<*{""}>) is now dumped properly.
-
-=item *
-
-L<diagnostics> has been upgraded from version 1.26 to version 1.27.
-
-See the entry for splain in the L</Utility Changes> section, for the
-changes. The diagnostics module and the splain utility are actually one
-and the same.
-
-=item *
-
-L<ExtUtils::Packlist> has been upgraded from version 1.45 to version 1.46.
-
-It no longer produces "used once" warnings when the C<read> and C<write>
-methods are called while the main program is still compiling (e.g., from
-within a BEGIN block) [perl #107410] [rt.cpan.org #50315].
-
-=item *
-
-L<Module::Pluggable> has been upgraded from version 3.9 to version 4.0.
-
-=item *
-
-L<overload> has been upgraded from version 1.16 to version 1.17.
-
-C<overload::Overloaded> no longer calls C<can> on the class, but uses
-another means to determine whether the object has overloading. It was
-never correct for it to call C<can>, as overloading does not respect
-AUTOLOAD. So classes that autoload methods and implement C<can> no longer
-have to account for overloading [perl #40333].
-
-=item *
-
-L<perlfaq> has been upgraded from version 5.0150036 to version 5.0150037.
-
-=item *
-
-L<PerlIO::scalar> has been upgraded from version 0.12 to version 0.13.
-
-(This is the module that implements C<< open $fh, '>', \$scalar >>.)
-
-It no longer assumes during C<seek> that $scalar is a string internally.
-If it didn't crash, it was close to doing so [perl #92706].
-
-Printing to an in-memory handle now works if the $scalar holds a reference,
-stringifying the reference before modifying it. References used to be
-treated as empty strings.
-
-Printing to an in-memory handle no longer crashes if the $scalar happens to
-hold a number internally, but no string buffer.
-
-=item *
-
-L<POSIX> has been upgraded from version 1.27 to version 1.29.
-
-C<sigsuspend> and C<pause> now run signals handle before returning, as the
-whole point of these two functions is to wait until a signal has
-arrived, and then return I<after> it has been triggered. Delayed, or
-"safe", signals were preventing that from happening, possibly resulting in
-race conditions [perl #107216].
-C<POSIX::sleep> is now a direct call into the underlying OS C<sleep>
-function, instead of being a Perl wrapper on C<CORE::sleep>. C<POSIX::dup2>
-now returns the correct value on Win32 (I<i.e.> the file descriptor).
-C<POSIX::SigSet> C<sigsuspend> and C<sigpending> and C<POSIX::pause> now
-dispatch safe signals immediately before returning to their caller.
-
-=item *
-
-L<Pod::Perldoc> has been upgraded from version 3.15_01 to version 3.15_15.
-
-=item *
-
-L<Term::UI> has been upgraded from version 0.26 to version 0.30.
-
-=item *
-
-L<Tie::File> has been upgraded from version 0.96 to version 0.98.
-
-=item *
-
-L<Unicode::UCD> has been upgraded from version 0.37 to version 0.38.
-This changes the output of C<prop_invmap()> for the Name_Alias property
-to reflect the changes that are planned for Unicode 6.1, so that there
-won't be a format change when upgrading to 6.1. Briefly, a second
-component of each alias is added that gives the type of alias it is.
-Examples are at L<Unicode::UCD/prop_invmap()>.
-
-=item *
-
-L<Version::Requirements> has been upgraded from version 0.101020 to version 0.101021.
-
-Version::Requirements is now DEPRECATED, use CPAN::Meta::Requirements,
-which is a drop-in replacement.
+L<Pod::Parser> has been upgraded from version 1.37 to version 1.50.
=back
However, any changes to F<pod/perldiag.pod> should go in the L</Diagnostics>
section.
-=head3 L<perlfunc>
-
-=over 4
-
-=item *
-
-C<dbmopen> treats a 0 mode as a special case, that prevents a nonexistent
-file from being created. This has been the case since Perl 5.000, but was
-never documented anywhere. Now the perlfunc entry mentions it
-[perl #90064].
-
-=item *
-
-The entry for C<split> has been rewritten. It is now far clearer than
-before.
-
-=back
-
-=head3 L<perlop> and L<perlsyn>
+=head3 L<XXX>
=over 4
=item *
-Documentation of the smartmatch operator has been reworked and moved from
-perlsyn to perlop where it belongs.
-
-=item *
-
-Documentation of the ellipsis statement (C<...>) has been reworked and
-moved from perlop to perlsyn.
+XXX Description of the change here
=back
=head2 New Diagnostics
-=over 4
-
-=item *
-
-L<Useless use of \E|perldiag/"Useless use of \E">
-
-C<\E> does nothing unless preceded by C<\Q>, C<\L> or C<\U>.
-
-=back
+XXX Newly added diagnostic messages go here
=head3 New Errors
=item *
-L<Cannot set tied @DB::args|perldiag/"Cannot set tied @DB::args">
-
-This error occurs when C<caller> tries to set C<@DB::args> but finds it
-tied. Before this error was added, it used to crash instead.
-
-=item *
-
-L<Cannot tie unreifiable array|perldiag/"Cannot tie unreifiable array">
-
-This error is part of a safety check that the C<tie> operator does before
-tying a special array like C<@_>. You should never see this message.
+XXX L<message|perldiag/"message">
=back
=item *
-L<defined(@array) is deprecated|perldiag/"defined(@array) is deprecated">
-
-The long-deprecated C<defined(@array)> now also warns for package variables.
-Previously it only issued a warning for lexical variables.
+XXX L<message|perldiag/"message">
=back
=back
-=head2 Removals
-
-=over 4
-
-=item *
-
-"sort is now a reserved word"
-
-This error used to occur when C<sort> was called without arguments, followed by C<;> or C<)>. (E.g., C<sort;> would die, but C<{sort}> was
-OK.) This error message was added in Perl 3 to catch code like
-C<close(sort)> which would no longer work. More than two decades later,
-this message is no longer appropriate. Now C<sort> without arguments is
-always allowed, and returns an empty list, as it did in those cases where
-it was already allowed [perl #90030].
-
-=back
-
=head1 Utility Changes
XXX Changes to installed programs such as F<perlbug> and F<xsubpp> go
entries for each change
Use L<XXX> with program names to get proper documentation linking. ]
-=head3 L<splain>
+=head3 L<XXX>
=over 4
=item *
-splain no longer emits backtraces with the first line number repeated.
-This:
-
- Uncaught exception from user code:
- Cannot fwiddle the fwuddle at -e line 1.
- at -e line 1
- main::baz() called at -e line 1
- main::bar() called at -e line 1
- main::foo() called at -e line 1
-
-has become this:
-
- Uncaught exception from user code:
- Cannot fwiddle the fwuddle at -e line 1.
- main::baz() called at -e line 1
- main::bar() called at -e line 1
- main::foo() called at -e line 1
-
-=item *
-
-Some error message consist of multiple lines that are listed as separate
-entries in L<perldiag>. splain has been taught to find the separate
-entries in these cases, instead of simply failing to find the message.
+XXX
=back
=item *
-The Pod files for the perl FAQ, L<perlxs>, L<perlxstut> and L<perldoc>
-are once again correctly installed in the same directory as the other core
-Pods.
-
-=for 5.16.0 This isn't a regression from 5.14.x, so don't mention this.
+XXX
=back
=item *
-F<t/porting/utils.t> now tests that various utility scripts compile cleanly.
-During development, this avoids the embarrassment of inadvertently pushing a
-commit which breaks code which isn't otherwise tested by the regression test
-suite. For example, F<installperl> and F<installman>, needed by
-C<make install>, are tested here.
+XXX
=back
=item *
-There are now feature bundle hints in C<PL_hints> (C<$^H>) that version
-declarations use, to avoid having to load F<feature.pm>. One setting of
-the hint bits indicates a "custom" feature bundle, which means that the
-entries in C<%^H> still apply. F<feature.pm> uses that.
-
-The C<HINT_FEATURE_MASK> macro is defined in F<perl.h> along with other
-hints. Other macros for setting and testing features and bundles are in
-the new F<feature.h>. C<FEATURE_IS_ENABLED> (which has moved to
-F<feature.h>) is no longer used throughout the codebase, but more specific
-macros, e.g., C<FEATURE_SAY_IS_ENABLED>, that are defined in F<feature.h>.
-
-=item *
-
-F<lib/feature.pm> is now a generated file, created by the new
-F<regen/feature.pl> script, which also generates F<feature.h>.
-
-=item *
-
-Tied arrays are now always C<AvREAL>. If C<@_> or C<DB::args> is tied, it
-is reified first, to make sure this is always the case.
+XXX
=back
=over 4
-=item * "b . COND" in the debugger has been fixed
-
-Breaking on the current line with C<b . COND> was broken by previous work and
-has now been fixed.
-
-=item * Tying C<%^H>
-
-Tying C<%^H> no longer causes perl to crash or ignore
-the contents of C<%^H> when entering a compilation
-scope [perl #106282].
-
-=item * C<~> on vstrings
-
-The bitwise complement operator (and possibly other operators, too) when
-passed a vstring would leave vstring magic attached to the return value,
-even though the string had changed. This meant that
-C<< version->new(~v1.2.3) >> would create a version looking like "v1.2.3"
-even though the string passed to C<< version->new >> was actually
-"\376\375\374". This also caused L<B::Deparse> to deparse C<~v1.2.3>
-incorrectly, without the C<~> [perl #29070].
-
-=item * Vstrings blowing away magic
-
-Assigning a vstring to a magic (e.g., tied, C<$!>) variable and then
-assigning something else used to blow away all the magic. This meant that
-tied variables would come undone, C<$!> would stop getting updated on
-failed system calls, C<$|> would stop setting autoflush, and other
-mischief would take place. This has been fixed.
-
-=item * C<newHVhv> and tied hashes
-
-The C<newHVhv> XS function now works on tied hashes, instead of crashing or
-returning an empty hash.
-
-=item * Hashes will null elements
-
-It is possible from XS code to create hashes with elements that have no
-values. Perl itself sometimes creates such hashes, but they are rarely
-visible to Perl code. The hash element and slice operators used to crash
-when handling these in lvalue context. These have been fixed. They now
-produce a "Modification of non-creatable hash value attempted" error
-message.
-
-=item * No warning for C<open(foo::bar)>
-
-When one writes C<open foo || die>, which used to work in Perl 4, a
-"Precedence problem" warning is produced. This warning used erroneously to
-apply to fully-qualified bareword handle names as well. This has been
-corrected.
-
-=item * C<select> and package aliasing
-
-After package aliasing (C<*foo:: = *bar::>), C<select> with 0 or 1 argument
-would sometimes return a name that could not be used to refer to the
-filehandle, or sometimes it would return C<undef> even when a filehandle
-was selected. Now it returns a typeglob reference in such cases.
-
-=item * C<PerlIO::get_layers> and tied variables
-
-C<PerlIO::get_layers> no longer ignores FETCH on tied variables as it used
-to most of the time [perl #97956].
-
-=item * C<PerlIO::get_layers> and numbers
-
-C<PerlIO::get_layers> no longer ignores some arguments that it thinks are
-numeric, while treating others as filehandle names. It is now consistent
-for flat scalars (i.e., not references).
-
-=item * Lvalue subs and strict mode
-
-Lvalue sub calls that are not determined to be such at compile time
-(C<&$name> or &{"name"}) are no longer exempt from strict refs if they
-occur in the last statement of an lvalue subroutine [perl #102486].
-
-=item * Non-lvalue sub calls in potentially lvalue context
-
-Sub calls whose subs are not visible at compile time, if
-they occurred in the last statement of an lvalue subroutine,
-would reject non-lvalue subroutines and die with "Can't modify non-lvalue
-subroutine call" [perl #102486].
-
-Non-lvalue sub calls whose subs I<are> visible at compile time exhibited
-the opposite bug. If the call occurred in the last statement of an lvalue
-subroutine, there would be no error when the lvalue sub was called in
-lvalue context. Perl would blindly assign to the temporary value returned
-by the non-lvalue subroutine.
-
-=item * AUTOLOADing lvalue subs
-
-C<AUTOLOAD> routines used to take precedence over the actual sub being
-called (i.e., when autoloading wasn't needed), for sub calls in lvalue or
-potential lvalue context, if the subroutine was not visible at compile
-time.
-
-=item * C<caller> and tied C<@DB::args>
-
-C<caller> sets C<@DB::args> to the subroutine arguments when called from
-the DB package. It used to crash when doing so if C<@DB::args> happened to
-be tied. Now it croaks instead.
-
-=item * Tying C<@_>
-
-Under debugging builds, this code:
-
- sub TIEARRAY{bless[]}
- sub {
- tie @_, "";
- \@_;
- }->(1);
-
-use to produce an "av_reify called on tied array" warning. It doesn't any
-more.
-
-=item * Unrecognised switches on C<#!> line
-
-If a switch, such as B<-x>, that cannot occur on the C<#!> line is used
-there, perl dies with "Can’t emulate...".
-
-It used to produce the same message for switches that perl did not
-recognise at all, whether on the command line or the C<#!> line.
-
-Now it produces the "Unrecognized switch" error message [perl #104288].
-
-=item * C<system> and SIGCHLD
-
-C<system> now temporarily blocks the SIGCHLD signal handler, to prevent the
-signal handler from stealing the exit status [perl #105700].
-
-=item * Deleting methods via C<delete>
-
-Deletion of methods via C<delete $Class::{method}> syntax used to update
-method caches if called in void context, but not scalar or list context.
-Now it always updates those caches.
-
-=item * Hash element deletion and destructors
-
-When hash elements are deleted in void context, the internal hash entry is
-now freed before the value is freed, to prevent destructors call by that
-latter freeing from seeing the hash in an inconsistent state. It was
-possible to cause double-frees if the destructor freed the hash itself
-[perl #100340].
-
-=item * C<(s)printf>'s %n formatting code
-
-The %n formatting code, which causes the number of characters to be
-assigned to the next argument to C<printf> or C<sprintf> now actually
-assigns the number of characters, instead of the number of bytes.
-
-It also works now with special lvalue functions like C<substr> and with
-nonexistent hash and array elements [perl #103492].
-
-=item * Typeglobs and threads
-
-Typeglobs returned from threads are no longer cloned if the parent thread
-already has a glob with the same name. This means that returned
-subroutines will now assign to the right package variables [perl #107366].
-
-=item * C<local $_>
-
-In Perl 5.14, C<local $_> was changed to create a new variable not tied to
-anything, even if $_ was tied before that. But, due to an oversight, it
-would still call FETCH once on a tied $_ before replacing it with the new
-variable. This has been fixed [perl #105912].
-
-=item * Returning tied variables
-
-When returning a value from a non-lvalue subroutine, Perl copies the value.
-Sometimes it cheats for the sake of speed, and does not copy the value if
-it makes no observable difference. This optimisation was erroneously
-allowing the copy to be skipped on tied variables, causing a difference in
-behaviour depending on the tied variable's reference count. This has been
-fixed [perl #95548].
-
-=item * C<{@a = sort}> no longer crashes
-
-This particular piece of code (C<sort> with no arguments assigned to an
-array, inside a block with no C<;>) started crashing in an earlier 5.15.x
-release. It has been fixed.
-
-=item * C<utf8::decode> and read-only scalars
-
-C<utf8::decode> now refuses to modify read-only scalars [perl #91850].
-
-=item * C<dbmopen> with undefined mode
-
-C<dbmopen> now only warns once, rather than three times, if the mode
-argument is C<undef> [perl #90064].
-
-=item * Freeing an aggregate during list assignment
-
-If list assignment to a hash or array triggered destructors that freed the
-hash or array itself, a crash would ensue. This is no longer the case
-[perl #107440].
-
-=item * Confused internal bookkeeping with @ISA arrays
-
-Creating a weak reference to an @ISA array or accessing the array index
-(C<$#ISA>) could result in confused internal bookkeeping for elements
-subsequently added to the @ISA array. For instance, creating a weak
-reference to the element itself could push that weak reference on to @ISA;
-and elements added after use of C<$#ISA> would be ignored by method lookup
-[perl #85670].
-
-=item * DELETE on scalar ties
-
-Tying an element of %ENV or C<%^H> and then deleting that element would
-result in a call to the tie object's DELETE method, even though tying the
-element itself is supposed to be equivalent to tying a scalar (the element
-is, of course, a scalar) [perl #67490].
-
-=item * Freeing $_ inside C<grep> or C<map>
-
-Freeing $_ inside a C<grep> or C<map> block or a code block embedded in a
-regular expression used to result in double frees [perl #92254, #92256].
-
-=item * Warnings with C<+=>
-
-The C<+=> operator does not usually warn when the left-hand side is
-C<undef>, but it was doing so for tied variables. This has been fixed
-[perl #44895].
-
-=item * Tying and Autovivification
+=item *
-When Perl autovivifies an element of a tied array or hash (which entails
-calling STORE with a new reference), it now calls FETCH immediately after
-the STORE, instead of assuming that FETCH would have returned the same
-reference. This can make it easier to implement tied objects [perl #35865, #43011].
+XXX
=back
XXX Generate this with:
- perl Porting/acknowledgements.pl v5.15.6..HEAD
+ perl Porting/acknowledgements.pl v5.15.7..HEAD
=head1 Reporting Bugs
https://perl5.git.perl.org / perl5.git / blobdiff