package feature;
-our $VERSION = '1.51';
+our $VERSION = '1.61';
our %feature = (
- fc => 'feature_fc',
- say => 'feature_say',
- state => 'feature_state',
- switch => 'feature_switch',
- bitwise => 'feature_bitwise',
- evalbytes => 'feature_evalbytes',
- array_base => 'feature_arybase',
- signatures => 'feature_signatures',
- current_sub => 'feature___SUB__',
- refaliasing => 'feature_refaliasing',
- postderef_qq => 'feature_postderef_qq',
- unicode_eval => 'feature_unieval',
- declared_refs => 'feature_myref',
- unicode_strings => 'feature_unicode',
+ fc => 'feature_fc',
+ isa => 'feature_isa',
+ say => 'feature_say',
+ state => 'feature_state',
+ switch => 'feature_switch',
+ bitwise => 'feature_bitwise',
+ indirect => 'feature_indirect',
+ evalbytes => 'feature_evalbytes',
+ signatures => 'feature_signatures',
+ current_sub => 'feature___SUB__',
+ refaliasing => 'feature_refaliasing',
+ postderef_qq => 'feature_postderef_qq',
+ unicode_eval => 'feature_unieval',
+ declared_refs => 'feature_myref',
+ unicode_strings => 'feature_unicode',
+ multidimensional => 'feature_multidimensional',
);
our %feature_bundle = (
- "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)],
- "5.23" => [qw(current_sub evalbytes fc postderef_qq say state switch unicode_eval unicode_strings)],
- "5.27" => [qw(bitwise current_sub evalbytes fc postderef_qq say state switch unicode_eval unicode_strings)],
- "all" => [qw(array_base bitwise current_sub declared_refs evalbytes fc postderef_qq refaliasing say signatures state switch unicode_eval unicode_strings)],
- "default" => [qw(array_base)],
+ "5.10" => [qw(indirect multidimensional say state switch)],
+ "5.11" => [qw(indirect multidimensional say state switch unicode_strings)],
+ "5.15" => [qw(current_sub evalbytes fc indirect multidimensional say state switch unicode_eval unicode_strings)],
+ "5.23" => [qw(current_sub evalbytes fc indirect multidimensional postderef_qq say state switch unicode_eval unicode_strings)],
+ "5.27" => [qw(bitwise current_sub evalbytes fc indirect multidimensional postderef_qq say state switch unicode_eval unicode_strings)],
+ "all" => [qw(bitwise current_sub declared_refs evalbytes fc indirect isa multidimensional postderef_qq refaliasing say signatures state switch unicode_eval unicode_strings)],
+ "default" => [qw(indirect multidimensional)],
);
$feature_bundle{"5.12"} = $feature_bundle{"5.11"};
$feature_bundle{"5.25"} = $feature_bundle{"5.23"};
$feature_bundle{"5.26"} = $feature_bundle{"5.23"};
$feature_bundle{"5.28"} = $feature_bundle{"5.27"};
+$feature_bundle{"5.29"} = $feature_bundle{"5.27"};
+$feature_bundle{"5.30"} = $feature_bundle{"5.27"};
+$feature_bundle{"5.31"} = $feature_bundle{"5.27"};
+$feature_bundle{"5.32"} = $feature_bundle{"5.27"};
+$feature_bundle{"5.33"} = $feature_bundle{"5.27"};
+$feature_bundle{"5.34"} = $feature_bundle{"5.27"};
$feature_bundle{"5.9.5"} = $feature_bundle{"5.10"};
my %noops = (
postderef => 1,
lexical_subs => 1,
);
+my %removed = (
+ array_base => 1,
+);
our $hint_shift = 26;
-our $hint_mask = 0x1c000000;
+our $hint_mask = 0x3c000000;
our @hint_bundles = qw( default 5.10 5.11 5.15 5.23 5.27 );
# This gets set (for now) in $^H as well as in %^H,
=head2 The 'say' feature
-C<use feature 'say'> tells the compiler to enable the Perl 6 style
+C<use feature 'say'> tells the compiler to enable the Raku-inspired
C<say> function.
See L<perlfunc/say> for details.
no warnings "experimental::smartmatch";
-C<use feature 'switch'> tells the compiler to enable the Perl 6
+C<use feature 'switch'> tells the compiler to enable the Raku
given/when construct.
See L<perlsyn/"Switch Statements"> for details.
=head2 The 'array_base' feature
-This feature supports the legacy C<$[> variable. See L<perlvar/$[> and
-L<arybase>. It is on by default but disabled under C<use v5.16> (see
-L</IMPLICIT LOADING>, below).
+This feature supported the legacy C<$[> variable. See L<perlvar/$[>.
+It was on by default but disabled under C<use v5.16> (see
+L</IMPLICIT LOADING>, below) and unavailable since perl 5.30.
This feature is available under this name starting with Perl 5.16. In
previous versions, it was simply on all the time, and this pragma knew
This feature is available from Perl 5.26 onwards.
+=head2 The 'isa' feature
+
+This allows the use of the C<isa> infix operator, which tests whether the
+scalar given by the left operand is an object of the class given by the
+right operand. See L<perlop/Class Instance Operator> for more details.
+
+This feature is available from Perl 5.32 onwards.
+
+=head2 The 'indirect' feature
+
+This feature allows the use of L<indirect object
+syntax|perlobj/Indirect Object Syntax> for method calls, e.g. C<new
+Foo 1, 2;>. It is enabled by default, but can be turned off to
+disallow indirect object syntax.
+
+This feature is available under this name from Perl 5.32 onwards. In
+previous versions, it was simply on all the time. To disallow (or
+warn on) indirect object syntax on older Perls, see the L<indirect>
+CPAN module.
+
+=head2 The 'multidimensional' feature
+
+This feature enables multidimensional array emulation, a perl 4 (or
+earlier) feature that was used to emulate multidimensional arrays with
+hashes. This works by converting code like C<< $foo{$x, y} >> into
+C<< $foo{join($;, $x, $y} >>. It is enabled by default, but can be
+turned off to disable multidimensional array emulation.
+
+When this feature is disabled the syntax that is normally replaced
+will report a compilation error.
+
+This feature is available under this name from Perl 5.34 onwards. In
+previous versions, it was simply on all the time.
+
+You can use the L<multidimensional> module on CPAN to disable
+multidimensional array emulation for older versions of Perl.
+
=head1 FEATURE BUNDLES
It's possible to load multiple features together, using
bundle features included
--------- -----------------
- :default array_base
+ :default indirect multidimensional
+
+ :5.10 indirect multidimensional say state switch
+
+ :5.12 indirect multidimensional say state switch
+ unicode_strings
- :5.10 say state switch array_base
+ :5.14 indirect multidimensional say state switch
+ unicode_strings
- :5.12 say state switch unicode_strings array_base
+ :5.16 current_sub evalbytes fc indirect
+ multidimensional say state switch
+ unicode_eval unicode_strings
- :5.14 say state switch unicode_strings array_base
+ :5.18 current_sub evalbytes fc indirect
+ multidimensional say state switch
+ unicode_eval unicode_strings
- :5.16 say state switch unicode_strings
- unicode_eval evalbytes current_sub fc
+ :5.20 current_sub evalbytes fc indirect
+ multidimensional say state switch
+ unicode_eval unicode_strings
- :5.18 say state switch unicode_strings
- unicode_eval evalbytes current_sub fc
+ :5.22 current_sub evalbytes fc indirect
+ multidimensional say state switch
+ unicode_eval unicode_strings
- :5.20 say state switch unicode_strings
- unicode_eval evalbytes current_sub fc
+ :5.24 current_sub evalbytes fc indirect
+ multidimensional postderef_qq say state
+ switch unicode_eval unicode_strings
- :5.22 say state switch unicode_strings
- unicode_eval evalbytes current_sub fc
+ :5.26 current_sub evalbytes fc indirect
+ multidimensional postderef_qq say state
+ switch unicode_eval unicode_strings
- :5.24 say state switch unicode_strings
- unicode_eval evalbytes current_sub fc
- postderef_qq
+ :5.28 bitwise current_sub evalbytes fc indirect
+ multidimensional postderef_qq say state
+ switch unicode_eval unicode_strings
- :5.26 say state switch unicode_strings
- unicode_eval evalbytes current_sub fc
- postderef_qq
+ :5.30 bitwise current_sub evalbytes fc indirect
+ multidimensional postderef_qq say state
+ switch unicode_eval unicode_strings
- :5.28 say state switch unicode_strings
- unicode_eval evalbytes current_sub fc
- postderef_qq bitwise
+ :5.32 bitwise current_sub evalbytes fc indirect
+ multidimensional postderef_qq say state
+ switch unicode_eval unicode_strings
+
+ :5.34 bitwise current_sub evalbytes fc indirect
+ multidimensional postderef_qq say state
+ switch unicode_eval unicode_strings
The C<:default> bundle represents the feature set that is enabled before
any C<use feature> or C<no feature> declaration.
If the required version is older than Perl 5.10, the ":default" feature
bundle is automatically loaded instead.
+Unlike C<use feature ":5.12">, saying C<use v5.12> (or any higher version)
+also does the equivalent of C<use strict>; see L<perlfunc/use> for details.
+
=back
=cut
my $import = shift;
my $bundle_number = $^H & $hint_mask;
my $features = $bundle_number != $hint_mask
- && $feature_bundle{$hint_bundles[$bundle_number >> $hint_shift]};
+ && $feature_bundle{$hint_bundles[$bundle_number >> $hint_shift]};
if ($features) {
# Features are enabled implicitly via bundle hints.
# Delete any keys that may be left over from last time.
if (exists $noops{$name}) {
next;
}
+ if (!$import && exists $removed{$name}) {
+ next;
+ }
unknown_feature($name);
}
if ($import) {