package feature;
-our $VERSION = '1.30';
+our $VERSION = '1.31';
our %feature = (
fc => 'feature_fc',
evalbytes => 'feature_evalbytes',
array_base => 'feature_arybase',
current_sub => 'feature___SUB__',
+ lexical_subs => 'feature_lexsubs',
unicode_eval => 'feature_unieval',
unicode_strings => 'feature_unicode',
);
"5.10" => [qw(array_base say state switch)],
"5.11" => [qw(array_base say state switch unicode_strings)],
"5.15" => [qw(current_sub evalbytes fc say state switch unicode_eval unicode_strings)],
- "all" => [qw(array_base current_sub evalbytes fc say state switch unicode_eval unicode_strings)],
+ "all" => [qw(array_base current_sub evalbytes fc lexical_subs say state switch unicode_eval unicode_strings)],
"default" => [qw(array_base)],
);
$feature_bundle{"5.17"} = $feature_bundle{"5.15"};
$feature_bundle{"5.18"} = $feature_bundle{"5.15"};
$feature_bundle{"5.9.5"} = $feature_bundle{"5.10"};
+my %experimental = (
+ lexical_subs => 1,
+);
our $hint_shift = 26;
our $hint_mask = 0x1c000000;
=head2 Lexical effect
Like other pragmas (C<use strict>, for example), features have a lexical
-effect. C<use feature qw(foo)> will only make the feature "foo" available
+effect. C<use feature qw(foo)> will only make the feature "foo" available
from that point to the end of the enclosing block.
{
This feature is available from Perl 5.16 onwards.
+=head2 The 'lexical_subs' feature
+
+B<WARNING>: This feature is still experimental and the implementation may
+change in future versions of Perl. For this reason, F<feature.pm> will
+warn when you enable the feature, unless you have explicitly disabled the
+warning:
+
+ no warnings "experimental::lexical_subs";
+
+This enables declaration of subroutines via C<my sub foo>, C<state sub foo>
+and C<our sub foo> syntax. See L<perlsub/Lexical Subroutines> for details.
+
+This feature is available from Perl 5.18 onwards.
+
=head1 FEATURE BUNDLES
It's possible to load multiple features together, using
if ($import) {
$^H{$feature{$name}} = 1;
$^H |= $hint_uni8bit if $name eq 'unicode_strings';
+ if ($experimental{$name}) {
+ require warnings;
+ warnings::warnif("experimental::$name",
+ "The $name feature is experimental");
+ }
} else {
delete $^H{$feature{$name}};
$^H &= ~ $hint_uni8bit if $name eq 'unicode_strings';