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Perlito5 - add minimal Exporter.pm; placeholder
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| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,235 @@ | ||
| package Exporter; | ||
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| use strict; | ||
| no strict 'refs'; | ||
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| our $Debug = 0; | ||
| our $ExportLevel = 0; | ||
| our $Verbose; | ||
| $Verbose ||= 0; | ||
| our $VERSION = '5.64_03'; | ||
| our %Cache; | ||
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| sub import { | ||
| my $pkg = shift; | ||
| my $callpkg = caller($ExportLevel); | ||
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| say "import: from $pkg to $callpkg [@_]"; | ||
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| if ( $pkg eq "Exporter" and @_ and $_[0] eq "import" ) { | ||
| *{ $callpkg . "::import" } = \&import; | ||
| return; | ||
| } | ||
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| return export( $pkg, $callpkg, @_ ); | ||
| } | ||
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| sub export_fail { | ||
| my $self = shift; | ||
| @_; | ||
| } | ||
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| # Heavy | ||
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| sub _rebuild_cache { | ||
| my ( $pkg, $exports, $cache ) = @_; | ||
| s/^&// foreach @$exports; | ||
| @{$cache}{@$exports} = (1) x @$exports; | ||
| my $ok = \@{"${pkg}::EXPORT_OK"}; | ||
| if (@$ok) { | ||
| s/^&// foreach @$ok; | ||
| @{$cache}{@$ok} = (1) x @$ok; | ||
| } | ||
| } | ||
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| sub export { | ||
| my ( $pkg, $callpkg, @imports ) = @_; | ||
| my ( $type, $sym, $cache_is_current, $oops ); | ||
| my ( $exports, $export_cache ) = ( \@{"${pkg}::EXPORT"}, $Exporter::Cache{$pkg} ||= {} ); | ||
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| if (@imports) { | ||
| if ( !%$export_cache ) { | ||
| _rebuild_cache( $pkg, $exports, $export_cache ); | ||
| $cache_is_current = 1; | ||
| } | ||
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| if ( grep m{^[/!:]}, @imports ) { | ||
| my $tagsref = \%{"${pkg}::EXPORT_TAGS"}; | ||
| my $tagdata; | ||
| my %imports; | ||
| my ( $remove, $spec, @names, @allexports ); | ||
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| # negated first item implies starting with default set: | ||
| unshift @imports, ':DEFAULT' if $imports[0] =~ m/^!/; | ||
| foreach $spec (@imports) { | ||
| $remove = $spec =~ s/^!//; | ||
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| if ( $spec =~ s/^:// ) { | ||
| if ( $spec eq 'DEFAULT' ) { | ||
| @names = @$exports; | ||
| } | ||
| elsif ( $tagdata = $tagsref->{$spec} ) { | ||
| @names = @$tagdata; | ||
| } | ||
| else { | ||
| warn qq["$spec" is not defined in %${pkg}::EXPORT_TAGS]; | ||
| ++$oops; | ||
| next; | ||
| } | ||
| } | ||
| elsif ( $spec =~ m:^\/(.*)\/$: ) { | ||
| my $patn = $1; | ||
| @allexports = keys %$export_cache unless @allexports; # only do keys once | ||
| @names = grep( /$patn/, @allexports ); # not anchored by default | ||
| } | ||
| else { | ||
| @names = ($spec); # is a normal symbol name | ||
| } | ||
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| warn "Import " . ( $remove ? "del" : "add" ) . ": @names " | ||
| if $Exporter::Verbose; | ||
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| if ($remove) { | ||
| foreach $sym (@names) { delete $imports{$sym} } | ||
| } | ||
| else { | ||
| @imports{@names} = (1) x @names; | ||
| } | ||
| } | ||
| @imports = keys %imports; | ||
| } | ||
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| my @carp; | ||
| foreach $sym (@imports) { | ||
| if ( !$export_cache->{$sym} ) { | ||
| if ( $sym =~ m/^\d/ ) { | ||
| $pkg->VERSION($sym); # inherit from UNIVERSAL | ||
| # If the version number was the only thing specified | ||
| # then we should act as if nothing was specified: | ||
| if ( @imports == 1 ) { | ||
| @imports = @$exports; | ||
| last; | ||
| } | ||
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| # We need a way to emulate 'use Foo ()' but still | ||
| # allow an easy version check: "use Foo 1.23, ''"; | ||
| if ( @imports == 2 and !$imports[1] ) { | ||
| @imports = (); | ||
| last; | ||
| } | ||
| } | ||
| elsif ( $sym !~ s/^&// || !$export_cache->{$sym} ) { | ||
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| # Last chance - see if they've updated EXPORT_OK since we | ||
| # cached it. | ||
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| unless ($cache_is_current) { | ||
| %$export_cache = (); | ||
| _rebuild_cache( $pkg, $exports, $export_cache ); | ||
| $cache_is_current = 1; | ||
| } | ||
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| if ( !$export_cache->{$sym} ) { | ||
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| # accumulate the non-exports | ||
| push @carp, qq["$sym" is not exported by the $pkg module\n]; | ||
| $oops++; | ||
| } | ||
| } | ||
| } | ||
| } | ||
| if ($oops) { | ||
| die ("@{carp}Can't continue after import errors"); | ||
| } | ||
| } | ||
| else { | ||
| @imports = @$exports; | ||
| } | ||
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| my ( $fail, $fail_cache ) = ( \@{"${pkg}::EXPORT_FAIL"}, $Exporter::FailCache{$pkg} ||= {} ); | ||
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| if (@$fail) { | ||
| if ( !%$fail_cache ) { | ||
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| # Build cache of symbols. Optimise the lookup by adding | ||
| # barewords twice... both with and without a leading &. | ||
| # (Technique could be applied to $export_cache at cost of memory) | ||
| my @expanded = map { /^\w/ ? ( $_, '&' . $_ ) : $_ } @$fail; | ||
| warn "${pkg}::EXPORT_FAIL cached: @expanded" if $Exporter::Verbose; | ||
| @{$fail_cache}{@expanded} = (1) x @expanded; | ||
| } | ||
| my @failed; | ||
| foreach $sym (@imports) { push( @failed, $sym ) if $fail_cache->{$sym} } | ||
| if (@failed) { | ||
| @failed = $pkg->export_fail(@failed); | ||
| foreach $sym (@failed) { | ||
| die ( qq["$sym" is not implemented by the $pkg module ], | ||
| "on this architecture" ); | ||
| } | ||
| if (@failed) { | ||
| die ("Can't continue after import errors"); | ||
| } | ||
| } | ||
| } | ||
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| warn "Importing into $callpkg from $pkg: ", join( ", ", sort @imports ) if $Exporter::Verbose; | ||
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| foreach $sym (@imports) { | ||
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| # shortcut for the common case of no type character | ||
| unless ( $sym =~ s/^(\W)// ) { | ||
| *{"${callpkg}::$sym"} = \&{"${pkg}::$sym"}; | ||
| next; | ||
| } | ||
| $type = $1; | ||
| no warnings 'once'; | ||
| *{"${callpkg}::$sym"} = | ||
| $type eq '&' ? \&{"${pkg}::$sym"} | ||
| : $type eq '$' ? \${"${pkg}::$sym"} | ||
| : $type eq '@' ? \@{"${pkg}::$sym"} | ||
| : $type eq '%' ? \%{"${pkg}::$sym"} | ||
| : $type eq '*' ? *{"${pkg}::$sym"} | ||
| : do { die ("Can't export symbol: $type$sym") }; | ||
| } | ||
| } | ||
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| sub export_to_level { | ||
| my $pkg = shift; | ||
| my $level = shift; | ||
| (undef) = shift; # XXX redundant arg | ||
| my $callpkg = caller($level); | ||
| $pkg->export( $callpkg, @_ ); | ||
| } | ||
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| # Utility functions | ||
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| sub _push_tags { | ||
| my ( $pkg, $var, $syms ) = @_; | ||
| my @nontag = (); | ||
| my $export_tags = \%{"${pkg}::EXPORT_TAGS"}; | ||
| push( | ||
| @{"${pkg}::$var"}, | ||
| map { $export_tags->{$_} ? @{ $export_tags->{$_} } : scalar( push( @nontag, $_ ), $_ ) } | ||
| (@$syms) ? @$syms : keys %$export_tags | ||
| ); | ||
| if ( @nontag and $^W ) { | ||
| die ( join( ", ", @nontag ) . " are not tags of $pkg" ); | ||
| } | ||
| } | ||
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| sub require_version { | ||
| my ( $self, $wanted ) = @_; | ||
| my $pkg = ref $self || $self; | ||
| return ${pkg}->VERSION($wanted); | ||
| } | ||
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| sub export_tags { | ||
| _push_tags( (caller)[0], "EXPORT", \@_ ); | ||
| } | ||
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| sub export_ok_tags { | ||
| _push_tags( (caller)[0], "EXPORT_OK", \@_ ); | ||
| } | ||
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| 1; | ||
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