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-rw-r--r--Master/tlpkg/tlperl/lib/feature.pm116
1 files changed, 61 insertions, 55 deletions
diff --git a/Master/tlpkg/tlperl/lib/feature.pm b/Master/tlpkg/tlperl/lib/feature.pm
index ec9fff7a6d4..ed13273f111 100644
--- a/Master/tlpkg/tlperl/lib/feature.pm
+++ b/Master/tlpkg/tlperl/lib/feature.pm
@@ -5,7 +5,7 @@
package feature;
-our $VERSION = '1.42';
+our $VERSION = '1.47';
our %feature = (
fc => 'feature_fc',
@@ -14,14 +14,13 @@ our %feature = (
switch => 'feature_switch',
bitwise => 'feature_bitwise',
evalbytes => 'feature_evalbytes',
- postderef => 'feature_postderef',
array_base => 'feature_arybase',
signatures => 'feature_signatures',
current_sub => 'feature___SUB__',
refaliasing => 'feature_refaliasing',
- lexical_subs => 'feature_lexsubs',
postderef_qq => 'feature_postderef_qq',
unicode_eval => 'feature_unieval',
+ declared_refs => 'feature_myref',
unicode_strings => 'feature_unicode',
);
@@ -30,7 +29,7 @@ our %feature_bundle = (
"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)],
- "all" => [qw(array_base bitwise current_sub evalbytes fc lexical_subs postderef postderef_qq refaliasing say signatures 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)],
);
@@ -45,7 +44,13 @@ $feature_bundle{"5.20"} = $feature_bundle{"5.15"};
$feature_bundle{"5.21"} = $feature_bundle{"5.15"};
$feature_bundle{"5.22"} = $feature_bundle{"5.15"};
$feature_bundle{"5.24"} = $feature_bundle{"5.23"};
+$feature_bundle{"5.25"} = $feature_bundle{"5.23"};
+$feature_bundle{"5.26"} = $feature_bundle{"5.23"};
$feature_bundle{"5.9.5"} = $feature_bundle{"5.10"};
+my %noops = (
+ postderef => 1,
+ lexical_subs => 1,
+);
our $hint_shift = 26;
our $hint_mask = 0x1c000000;
@@ -169,54 +174,28 @@ potentially using Unicode in your program, the
C<use feature 'unicode_strings'> subpragma is B<strongly> recommended.
This feature is available starting with Perl 5.12; was almost fully
-implemented in Perl 5.14; and extended in Perl 5.16 to cover C<quotemeta>.
+implemented in Perl 5.14; and extended in Perl 5.16 to cover C<quotemeta>;
+and extended further in Perl 5.26 to cover L<the range
+operator|perlop/Range Operators>.
=head2 The 'unicode_eval' and 'evalbytes' features
-Under the C<unicode_eval> feature, Perl's C<eval> function, when passed a
-string, will evaluate it as a string of characters, ignoring any
-C<use utf8> declarations. C<use utf8> exists to declare the encoding of
-the script, which only makes sense for a stream of bytes, not a string of
-characters. Source filters are forbidden, as they also really only make
-sense on strings of bytes. Any attempt to activate a source filter will
-result in an error.
-
-The C<evalbytes> feature enables the C<evalbytes> keyword, which evaluates
-the argument passed to it as a string of bytes. It dies if the string
-contains any characters outside the 8-bit range. Source filters work
-within C<evalbytes>: they apply to the contents of the string being
-evaluated.
-
-Together, these two features are intended to replace the historical C<eval>
-function, which has (at least) two bugs in it, that cannot easily be fixed
-without breaking existing programs:
-
-=over
-
-=item *
-
-C<eval> behaves differently depending on the internal encoding of the
-string, sometimes treating its argument as a string of bytes, and sometimes
-as a string of characters.
-
-=item *
-
-Source filters activated within C<eval> leak out into whichever I<file>
-scope is currently being compiled. To give an example with the CPAN module
-L<Semi::Semicolons>:
-
- BEGIN { eval "use Semi::Semicolons; # not filtered here " }
- # filtered here!
-
-C<evalbytes> fixes that to work the way one would expect:
+Together, these two features are intended to replace the legacy string
+C<eval> function, which behaves problematically in some instances. They are
+available starting with Perl 5.16, and are enabled by default by a
+S<C<use 5.16>> or higher declaration.
- use feature "evalbytes";
- BEGIN { evalbytes "use Semi::Semicolons; # filtered " }
- # not filtered
-
-=back
+C<unicode_eval> changes the behavior of plain string C<eval> to work more
+consistently, especially in the Unicode world. Certain (mis)behaviors
+couldn't be changed without breaking some things that had come to rely on
+them, so the feature can be enabled and disabled. Details are at
+L<perlfunc/Under the "unicode_eval" feature>.
-These two features are available starting with Perl 5.16.
+C<evalbytes> is like string C<eval>, but operating on a byte stream that is
+not UTF-8 encoded. Details are at L<perlfunc/evalbytes EXPR>. Without a
+S<C<use feature 'evalbytes'>> nor a S<C<use v5.16>> (or higher) declaration in
+the current scope, you can still access it by instead writing
+C<CORE::evalbytes>.
=head2 The 'current_sub' feature
@@ -246,17 +225,21 @@ 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, Perl will
-warn when you use the feature, unless you have explicitly disabled the
-warning:
+In Perl versions prior to 5.26, this feature enabled
+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.
- no warnings "experimental::lexical_subs";
+This feature is available from Perl 5.18 onwards. From Perl 5.18 to 5.24,
+it was classed as experimental, and Perl emitted a warning for its
+usage, except when explicitly disabled:
-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.
+ no warnings "experimental::lexical_subs";
-This feature is available from Perl 5.18 onwards.
+As of Perl 5.26, use of this feature no longer triggers a warning, though
+the C<experimental::lexical_subs> warning category still exists (for
+compatibility with code that disables it). In addition, this syntax is
+not only no longer experimental, but it is enabled for all Perl code,
+regardless of what feature declarations are in scope.
=head2 The 'postderef' and 'postderef_qq' features
@@ -346,6 +329,22 @@ See L<perlop/Bitwise String Operators> for details.
This feature is available from Perl 5.22 onwards.
+=head2 The 'declared_refs' feature
+
+B<WARNING>: This feature is still experimental and the implementation may
+change in future versions of Perl. For this reason, Perl will
+warn when you use the feature, unless you have explicitly disabled the
+warning:
+
+ no warnings "experimental::declared_refs";
+
+This allows a reference to a variable to be declared with C<my>, C<state>,
+our C<our>, or localized with C<local>. It is intended mainly for use in
+conjunction with the "refaliasing" feature. See L<perlref/Declaring a
+Reference to a Variable> for examples.
+
+This feature is available from Perl 5.26 onwards.
+
=head1 FEATURE BUNDLES
It's possible to load multiple features together, using
@@ -382,6 +381,10 @@ The following feature bundles are available:
unicode_eval evalbytes current_sub fc
postderef_qq
+ :5.26 say state switch unicode_strings
+ unicode_eval evalbytes current_sub fc
+ postderef_qq
+
The C<:default> bundle represents the feature set that is enabled before
any C<use feature> or C<no feature> declaration.
@@ -487,6 +490,9 @@ sub __common {
next;
}
if (!exists $feature{$name}) {
+ if (exists $noops{$name}) {
+ next;
+ }
unknown_feature($name);
}
if ($import) {