=encoding utf8

=head1 NAME

perldelta - what is new for perl v5.41.7

=head1 DESCRIPTION

This document describes differences between the 5.41.6 release and the 5.41.7
release.

If you are upgrading from an earlier release such as 5.41.5, first read
L<perl5416delta>, which describes differences between 5.41.5 and 5.41.6.

=head1 Core Enhancements

=head2 New C<:writer> attribute on field variables

Classes defined using C<use feature 'class'> are now able to automatically
create writer accessors for scalar fields, by using the C<:writer> attribute,
similar to the way that C<:reader> already creates reader accessors.

    class Point {
        field $x :reader :writer :param;
        field $y :reader :writer :param;
    }

    my $p = Point->new( x => 20, y => 40 );
    $p->set_x(60);

=head2 New C<any> and C<all> operators

A new experimental feature has been added, which adds two new list-processing
operators, C<any> and C<all>.

    use v5.40;
    use feature 'all';

    my @numbers = ...

    if(all { $_ % 2 == 0 } @numbers) {
        say "All the numbers are even";
    }

These operate similarly to C<grep> except that they only ever return true or
false, testing if any (or all) of the elements in the list make the testing
block yield true.  Because of this they can short-circuit, avoiding the need
to test any further elements if a given element determines the eventual
result.

These are inspired by the same-named functions in the L<List::Util> module,
except that they are implemented as direct core operators, and thus perform
faster, and do not produce an additional subroutine call stack frame for
invoking the code block.

=head1 Performance Enhancements

=over 4

=item *

Code that uses the C<indexed> function from the L<builtin> module to generate
a list of index/value pairs out of an array or list which is then passed into
a two-variable C<foreach> list to unpack those again is now optimised to be
more efficient.

    my @array = (...);

    foreach my ($idx, $val) (builtin::indexed @array) {
        ...
    }

Z<>

    foreach my ($idx, $val) (builtin::indexed LIST...) {
        ...
    }

In particular, a temporary list twice the size of the original is no longer
generated.  Instead, the loop iterates down the original array or list
in-place directly, in the same way that C<foreach (@array)> or
C<foreach (LIST)> would do.

=back

=head1 Modules and Pragmata

=head2 Updated Modules and Pragmata

=over 4

=item *

L<B::Deparse> has been upgraded from version 1.80 to 1.81.

=item *

L<builtin> has been upgraded from version 0.016 to 0.017.

=item *

L<CPAN::Meta::YAML> has been upgraded from version 0.018 to 0.020.

=item *

L<feature> has been upgraded from version 1.92 to 1.93.

=item *

L<IO::Socket::IP> has been upgraded from version 0.42 to 0.43.

=item *

L<Module::CoreList> has been upgraded from version 5.20241120 to 5.20241220.

=item *

L<Opcode> has been upgraded from version 1.66 to 1.67.

=item *

L<parent> has been upgraded from version 0.242_001 to 0.244.

=item *

L<warnings> has been upgraded from version 1.71 to 1.72.

=item *

L<XS::APItest> has been upgraded from version 1.38 to 1.40.

=back

=head1 Documentation

=head2 Changes to Existing Documentation

We have attempted to update the documentation to reflect the changes
listed in this document. If you find any we have missed, open an issue
at L<https://github.com/Perl/perl5/issues>.

Additionally, the following selected changes have been made:

=head3 L<perl5416delta>

=head4 F<pod/perlguts.pod> and F<pod/perlclib.pod>

=over 4

=item Memory Allocation in C/XS

Documentation was updated to reflect that mixing C<Newx>, C<Renew>, and
C<Safefree> vs C<malloc>, C<realloc>, and C<free> are not allowed, and mixing
pointers between the 2 classes of APIs is not allowed. Updates made in
F<pod/perlguts.pod> and F<pod/perlclib.pod>.

=back

=over 4

=item
Added the change note for apostrophes in names being reinstated, which
was delayed by the review cycle.

=back



=head1 Configuration and Compilation

=over 4

=item *

The (mostly undocumented) configuration macro C<PERL_STRICT_CR> has been
removed. When enabled (e.g. with C<./Configure -A ccflags=-DPERL_STRICT_CR>),
it would make the perl parser throw a fatal error when it encountered a CR
(carriage return) character in source files. The default (and now only)
behavior of the perl parser is to strip CRs paired with newline characters and
otherwise treat them as whitespace.

(C<PERL_STRICT_CR> was originally introduced in perl 5.005 to optionally
restore backward compatibility with perl 5.004, which had made CR in source
files an error. Before that, CR was accepted, but retained literally in quoted
multi-line constructs such as here-documents, even at the end of a line.)

=item *

Similarly, the (even less documented) configuration macro C<PERL_CR_FILTER> has
been removed. When enabled, it would install a default source filter to strip
carriage returns from source code before the parser proper got to see it.

=back

=head1 Testing

Tests were added and changed to reflect the other additions and changes
in this release.

=head1 Internal Changes

=over 4

=item *

New API functions are introduced to convert strings encoded in UTF-8 to
their ordinal code point equivalent.  These are safe to use by default,
and generally more convenient to use than the existing ones.

L<perlapi/C<utf8_to_uv>> and L<perlapi/C<utf8_to_uv_or_die>> replace
L<perlapi/C<utf8_to_uvchr>> (which is retained for backwards
compatibility), but you should convert to use the new forms, as likely
you aren't using the old one safely.

To convert in the opposite direction, you can now use
L<perlapi/C<uv_to_utf8>>.  This is not a new function, but a new synonym
for L<perlapi/C<uvchr_to_utf8>>.  It is added so you don't have to learn
two sets of names.

There are also two new functions, L<perlapi/C<strict_utf8_to_uv>> and
L<perlapi/C<c9strict_utf8_to_uv>> which do the same thing except when
the input string represents a code point that Unicode doesn't accept as
legal for interchange, using either the strict original definition
(C<strict_utf8_to_uv>), or the looser one given by
L<Unicode Corrigendum #9|https://www.unicode.org/versions/corrigendum9.html>
(C<c9strict_utf8_to_uv>).  When the input string represents one of the
restricted code points, these functions return the Unicode
C<REPLACEMENT CHARACTER> instead.

Also L<perlapi/C<extended_utf8_to_uv>> is a synonym for C<utf8_to_uv>, for use
when you want to emphasize that the entire range of Perl extended UTF-8
is acceptable.

There are also replacement functions for the three more specialized
conversion functions that you are unlikely to need to use.  Again, the
old forms are kept for backwards compatibility, but you should convert
to use the new forms.

L<perlapi/C<utf8_to_uv_flags>> replaces L<perlapi/C<utf8n_to_uvchr>>.

L<perlapi/C<utf8_to_uv_errors>> replaces L<perlapi/C<utf8n_to_uvchr_error>>.

L<perlapi/C<utf8_to_uv_msgs>> replaces
L<perlapi/C<utf8n_to_uvchr_msgs>>.

Also added are the inverse functions L<perlapi/C<uv_to_utf8_flags>>
and L<perlapi/C<uv_to_utf8_msgs>>, which are synonyms for the existing
functions, L<perlapi/C<uvchr_to_utf8_flags>> and
L<perlapi/C<uvchr_to_utf8_flags_msgs>> respectively.  These are provided only
so you don't have to learn two sets of names.

=item *

Three new API functions are introduced to convert strings encoded in
UTF-8 to native bytes format (if possible).  These are easier to use
than the existing ones, and they avoid unnecessary memory allocations.
The functions are L<perlapi/C<utf8_to_bytes_overwrite>> which is used
when it is ok for the input string to be overwritten with the converted
result; and L<perlapi/C<utf8_to_bytes_new_pv>> and
L<perlapi/C<utf8_to_bytes_temp_pv>> when the original string must be
preserved intact.  C<utf8_to_bytes_temp_pv> returns the result in a
temporary using L<perlapi>/C<SAVEFREEPV> that will automatically be
destroyed.  With C<utf8_to_bytes_new_pv>, you are responsible for
freeing the newly allocated memory that is returned if the conversion is
successful.

The latter two functions are designed to replace
L<perlapi/C<bytes_from_utf8>> which creates memory unnecessarily, or
unnecessarily large.

=item *

New API functions L<C<valid_identifier_pve()>|perlapi/valid_identifier_pve>,
L<C<valid_identifier_pvn()>|perlapi/valid_identifier_pvn> and
L<C<valid_identifier_sv()>|perlapi/valid_identifier_sv> have been added, which
test if a string would be considered by Perl to be a valid identifier name.

=item *

When assigning from an SVt_IV into a SVt_NV (or vice versa), providing that
both are "bodyless" types, Perl_sv_setsv_flags will now just change the
destination type to match the source type. Previously, an SVt_IV would have
been upgraded to a SVt_PVNV to store an NV, and an SVt_NV would have been
upgraded to a SVt_PVIV to store an IV. This change prevents the need to
allocate - and later free - the relevant body struct.

=back

=head1 Selected Bug Fixes

=over 4

=item *

Declaring a lexically scoped array or hash using C<state> within a subroutine
and then immediately returning no longer triggers a "Bizarre copy of HASH/ARRAY
in subroutine exit" error. [GH #18630]

=item *

C<builtin::trim()> didn't properly clear C<TARG> which could result in
out of date cached numeric versions of the value being used on a
second evaluation.  Properly clear any cached values. [GH #22784]

=back

=head1 Acknowledgements

Perl 5.41.7 represents approximately 4 weeks of development since Perl
5.41.6 and contains approximately 11,000 lines of changes across 160 files
from 16 authors.

Excluding auto-generated files, documentation and release tools, there were
approximately 6,400 lines of changes to 96 .pm, .t, .c and .h files.

Perl continues to flourish into its fourth decade thanks to a vibrant
community of users and developers. The following people are known to have
contributed the improvements that became Perl 5.41.7:

Dagfinn Ilmari Mannsåker, Daniel Dragan, Ed Sabol, James E Keenan, Karen
Etheridge, Karl Williamson, Lukas Mai, Mark Fowler, Max Maischein, Paul
Evans, Richard Leach, Scott Baker, Sisyphus, TAKAI Kousuke, Thibault
Duponchelle, Tony Cook.

The list above is almost certainly incomplete as it is automatically
generated from version control history. In particular, it does not include
the names of the (very much appreciated) contributors who reported issues to
the Perl bug tracker.

Many of the changes included in this version originated in the CPAN modules
included in Perl's core. We're grateful to the entire CPAN community for
helping Perl to flourish.

For a more complete list of all of Perl's historical contributors, please
see the F<AUTHORS> file in the Perl source distribution.

=head1 Reporting Bugs

If you find what you think is a bug, you might check the perl bug database
at L<https://github.com/Perl/perl5/issues>. There may also be information at
L<https://www.perl.org/>, the Perl Home Page.

If you believe you have an unreported bug, please open an issue at
L<https://github.com/Perl/perl5/issues>. Be sure to trim your bug down to a
tiny but sufficient test case.

If the bug you are reporting has security implications which make it
inappropriate to send to a public issue tracker, then see
L<perlsec/SECURITY VULNERABILITY CONTACT INFORMATION>
for details of how to report the issue.

=head1 Give Thanks

If you wish to thank the Perl 5 Porters for the work we had done in Perl 5,
you can do so by running the C<perlthanks> program:

    perlthanks

This will send an email to the Perl 5 Porters list with your show of thanks.

=head1 SEE ALSO

The F<Changes> file for an explanation of how to view exhaustive details on
what changed.

The F<INSTALL> file for how to build Perl.

The F<README> file for general stuff.

The F<Artistic> and F<Copying> files for copyright information.

=cut
