X-Git-Url: https://perl5.git.perl.org/perl5.git/blobdiff_plain/c6b36e452c0b3d11d99efcc36f6a80394940f0c3..5a6bb681360972ef854d7b6b457148c9b1aa61a8:/regen/feature.pl diff --git a/regen/feature.pl b/regen/feature.pl index f4e8d1e..c9a4cd6 100755 --- a/regen/feature.pl +++ b/regen/feature.pl @@ -5,7 +5,8 @@ # lib/feature.pm # feature.h # -# from information hardcoded into this script. +# from information hardcoded into this script and from two #defines +# in perl.h. # # This script is normally invoked from regen.pl. @@ -25,38 +26,51 @@ my %feature = ( state => 'state', switch => 'switch', evalbytes => 'evalbytes', + postderef => 'postderef', + array_base => 'arybase', current_sub => '__SUB__', + lexical_subs => 'lexsubs', + postderef_qq => 'postderef_qq', unicode_eval => 'unieval', unicode_strings => 'unicode', -); - -# These work backwards--the presence of the hint elem disables the feature: -my %default_feature = ( - array_base => 'noarybase', + fc => 'fc', + signatures => 'signatures', ); # NOTE: If a feature is ever enabled in a non-contiguous range of Perl # versions, any code below that uses %BundleRanges will have to # be changed to account. +# 5.odd implies the next 5.even, but an explicit 5.even can override it. my %feature_bundle = ( - default => [keys %default_feature], + all => [ keys %feature ], + default => [qw(array_base)], "5.9.5" => [qw(say state switch array_base)], "5.10" => [qw(say state switch array_base)], "5.11" => [qw(say state switch unicode_strings array_base)], - "5.12" => [qw(say state switch unicode_strings array_base)], "5.13" => [qw(say state switch unicode_strings array_base)], - "5.14" => [qw(say state switch unicode_strings array_base)], "5.15" => [qw(say state switch unicode_strings unicode_eval - evalbytes current_sub)], - "5.16" => [qw(say state switch unicode_strings unicode_eval - evalbytes current_sub)], + evalbytes current_sub fc)], + "5.17" => [qw(say state switch unicode_strings unicode_eval + evalbytes current_sub fc)], + "5.19" => [qw(say state switch unicode_strings unicode_eval + evalbytes current_sub fc)], + "5.21" => [qw(say state switch unicode_strings unicode_eval + evalbytes current_sub fc)], ); +# not actually used currently +my @experimental = qw( lexical_subs ); + ########################################################################### # More data generated from the above +for (keys %feature_bundle) { + next unless /^5\.(\d*[13579])\z/; + $feature_bundle{"5.".($1+1)} ||= $feature_bundle{$_}; +} + my %UniqueBundles; # "say state switch" => 5.10 my %Aliases; # 5.12 => 5.11 for( sort keys %feature_bundle ) { @@ -87,12 +101,17 @@ for my $bund ( my $HintShift; my $HintMask; +my $Uni8Bit; open "perl.h", "perl.h" or die "$0 cannot open perl.h: $!"; -perlh: { - while (readline "perl.h") { - next unless /#define\s+HINT_FEATURE_MASK/; - /(0x[A-Fa-f0-9]+)/ or die "No hex number in:\n\n$_\n "; +while (readline "perl.h") { + next unless /#\s*define\s+(HINT_FEATURE_MASK|HINT_UNI_8_BIT)/; + my $is_u8b = $1 =~ 8; + /(0x[A-Fa-f0-9]+)/ or die "No hex number in:\n\n$_\n "; + if ($is_u8b) { + $Uni8Bit = $1; + } + else { my $hex = $HintMask = $1; my $bits = sprintf "%b", oct $1; $bits =~ /^0*1+(0*)\z/ @@ -102,11 +121,13 @@ perlh: { length sprintf "%b", scalar keys %UniqueBundles; $bits =~ /1{$bits_needed}/ or die "Not enough bits (need $bits_needed)" - . " in $bits (binary for $hex):\n\n$_\n"; - last perlh; + . " in $bits (binary for $hex):\n\n$_\n "; } - die "No HINT_FEATURE_MASK defined in perl.h"; + if ($Uni8Bit && $HintMask) { last } } +die "No HINT_FEATURE_MASK defined in perl.h" unless $HintMask; +die "No HINT_UNI_8_BIT defined in perl.h" unless $Uni8Bit; + close "perl.h"; my @HintedBundles = @@ -139,22 +160,14 @@ sub longest { $long; } -print $pm "my %feature = (\n"; +print $pm "our %feature = (\n"; my $width = length longest keys %feature; -for(sort { length $a <=> length $b } keys %feature) { +for(sort { length $a <=> length $b || $a cmp $b } keys %feature) { print $pm " $_" . " "x($width-length) . " => 'feature_$feature{$_}',\n"; } print $pm ");\n\n"; -print $pm "my %default_feature = (\n"; -$width = length longest keys %default_feature; -for(sort { length $a <=> length $b } keys %default_feature) { - print $pm " $_" . " "x($width-length) - . " => 'feature_$default_feature{$_}',\n"; -} -print $pm ");\n\n"; - print $pm "our %feature_bundle = (\n"; $width = length longest values %UniqueBundles; for( sort { $UniqueBundles{$a} cmp $UniqueBundles{$b} } @@ -170,11 +183,20 @@ for (sort keys %Aliases) { qq'\$feature_bundle{"$_"} = \$feature_bundle{"$Aliases{$_}"};\n'; }; +#print $pm "my \%experimental = (\n"; +#print $pm " $_ => 1,\n", for @experimental; +#print $pm ");\n"; + print $pm <> HINT_FEATURE_SHIFT) -#define CURRENT_HINTS \\ +#define CURRENT_HINTS \ (PL_curcop == &PL_compiling ? PL_hints : PL_curcop->cop_hints) -#define CURRENT_FEATURE_BUNDLE (CURRENT_HINTS >> HINT_FEATURE_SHIFT) - +#define CURRENT_FEATURE_BUNDLE \ + ((CURRENT_HINTS & HINT_FEATURE_MASK) >> HINT_FEATURE_SHIFT) + +/* Avoid using ... && Perl_feature_is_enabled(...) as that triggers a bug in + the HP-UX cc on PA-RISC */ +#define FEATURE_IS_ENABLED(name) \ + ((CURRENT_HINTS \ + & HINT_LOCALIZE_HH) \ + ? Perl_feature_is_enabled(aTHX_ STR_WITH_LEN(name)) : FALSE) +/* The longest string we pass in. */ EOH +my $longest_internal_feature_name = longest values %feature; +print $h < length $b } keys %feature, keys %default_feature + sort { length $a <=> length $b || $a cmp $b } keys %feature ) { my($first,$last) = map { (my $__ = uc) =~ y/.//d; $__ } @{$BundleRanges{$_}}; - my $default = ''; - my $name = $feature{$_} # skip "no" - || ($default = '_d', substr $default_feature{$_}, 2); + my $name = $feature{$_}; my $NAME = uc $name; if ($last && $first eq 'DEFAULT') { # ‘>= DEFAULT’ warns print $h <= FEATURE_BUNDLE_$first && \\ CURRENT_FEATURE_BUNDLE <= FEATURE_BUNDLE_$last) \\ || (CURRENT_FEATURE_BUNDLE == FEATURE_BUNDLE_CUSTOM && \\ - FEATURE_IS_ENABLED$default("$name")) \\ + FEATURE_IS_ENABLED("$name")) \\ ) EOH3 } - else { + elsif ($first) { print $h < 5.011 + (my $macrover = $_) =~ y/.//d; + print $h <<" EOK"; + (sv_setnv(comp_ver, $numver), + vcmp(ver, upg_version(comp_ver, FALSE)) >= 0) + ? FEATURE_BUNDLE_$macrover : + EOK +} + +print $h < 2) @@ -333,7 +402,7 @@ pragma.) =head2 Lexical effect Like other pragmas (C, for example), features have a lexical -effect. C will only make the feature "foo" available +effect. C will only make the feature "foo" available from that point to the end of the enclosing block. { @@ -355,7 +424,8 @@ has lexical effect. } say "Yet it is here."; -C with no features specified will turn off all features. +C with no features specified will reset to the default group. To +disable I features (an unusual request!) use C. =head1 AVAILABLE FEATURES @@ -382,28 +452,29 @@ This feature is available starting with Perl 5.10. C tells the compiler to enable the Perl 6 given/when construct. -See L for details. +See L for details. This feature is available starting with Perl 5.10. =head2 The 'unicode_strings' feature -C tells the compiler to use Unicode semantics +C tells the compiler to use Unicode rules in all string operations executed within its scope (unless they are also within the scope of either C or C). The same applies to all regular expressions compiled within the scope, even if executed outside -it. +it. It does not change the internal representation of strings, but only how +they are interpreted. C tells the compiler to use the traditional -Perl semantics wherein the native character set semantics is used unless it is +Perl rules wherein the native character set rules is used unless it is clear to Perl that Unicode is desired. This can lead to some surprises when the behavior suddenly changes. (See L for details.) For this reason, if you are potentially using Unicode in your program, the C subpragma is B recommended. -This feature is available starting with Perl 5.12, but was not fully -implemented until Perl 5.14. +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. =head2 The 'unicode_eval' and 'evalbytes' features @@ -469,6 +540,49 @@ 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 nothing about it. +=head2 The 'fc' feature + +C tells the compiler to enable the C function, +which implements Unicode casefolding. + +See L for details. + +This feature is available from Perl 5.16 onwards. + +=head2 The 'lexical_subs' feature + +B: 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::lexical_subs"; + +This enables declaration of subroutines via C, C +and C syntax. See L for details. + +This feature is available from Perl 5.18 onwards. + +=head2 The 'signatures' feature + +B: 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::signatures"; + +This enables unpacking of subroutine arguments into lexical variables +by syntax such as + + sub foo ($left, $right) { + return $left + $right; + } + +See L for details. + +This feature is available from Perl 5.20 onwards. + =head1 FEATURE BUNDLES It's possible to load multiple features together, using @@ -515,7 +629,7 @@ the C construct. That is, will do an implicit - no feature; + no feature ':all'; use feature ':5.10'; and so on. Note how the trailing sub-version @@ -535,64 +649,44 @@ bundle is automatically loaded instead. =cut -sub current_bundle { - my $bundle_number = $^H & $hint_mask; - return if $bundle_number == $hint_mask; - return $feature_bundle{@hint_bundles[$bundle_number >> $hint_shift]}; -} - sub import { my $class = shift; - if (@_ == 0) { + + if (!@_) { croak("No features specified"); } - if (my $features = current_bundle) { - # Features are enabled implicitly via bundle hints - unshift @_, @$features; - $^H |= $hint_mask; - } - while (@_) { - my $name = shift(@_); - if (substr($name, 0, 1) eq ":") { - my $v = substr($name, 1); - if (!exists $feature_bundle{$v}) { - $v =~ s/^([0-9]+)\.([0-9]+).[0-9]+$/$1.$2/; - if (!exists $feature_bundle{$v}) { - unknown_feature_bundle(substr($name, 1)); - } - } - unshift @_, @{$feature_bundle{$v}}; - next; - } - if (!exists $feature{$name}) { - if (!exists $default_feature{$name}) { - unknown_feature($name); - } - delete $^H{$default_feature{$name}}; next; - } - $^H{$feature{$name}} = 1; - $^H |= $hint_uni8bit if $name eq 'unicode_strings'; - } + + __common(1, @_); } sub unimport { my $class = shift; - if (my $features = current_bundle) { - # Features are enabled implicitly via bundle hints - # Pass them to import() to put them in a form we can handle. - import(undef, @$features); - $^H |= $hint_mask; - } - - # A bare C should disable *all* features + # A bare C should reset to the default bundle if (!@_) { - delete @^H{ values(%feature) }; - $^H &= ~ $hint_uni8bit; - @^H{ values(%default_feature) } = (1) x keys %default_feature; - return; + $^H &= ~($hint_uni8bit|$hint_mask); + return; } + __common(0, @_); +} + + +sub __common { + my $import = shift; + my $bundle_number = $^H & $hint_mask; + my $features = $bundle_number != $hint_mask + && $feature_bundle{$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. + delete @^H{ values(%feature) }; + $^H |= $hint_mask; + for (@$features) { + $^H{$feature{$_}} = 1; + $^H |= $hint_uni8bit if $_ eq 'unicode_strings'; + } + } while (@_) { my $name = shift; if (substr($name, 0, 1) eq ":") { @@ -606,13 +700,13 @@ sub unimport { unshift @_, @{$feature_bundle{$v}}; next; } - if (!exists($feature{$name})) { - if (!exists $default_feature{$name}) { + if (!exists $feature{$name}) { unknown_feature($name); - } - $^H{$default_feature{$name}} = 1; next; } - else { + if ($import) { + $^H{$feature{$name}} = 1; + $^H |= $hint_uni8bit if $name eq 'unicode_strings'; + } else { delete $^H{$feature{$name}}; $^H &= ~ $hint_uni8bit if $name eq 'unicode_strings'; }