package Exporter::Heavy; use strict; no strict 'refs'; # On one line so MakeMaker will see it. require Exporter; our $VERSION = $Exporter::VERSION; =head1 NAME Exporter::Heavy - Exporter guts =head1 SYNOPSIS (internal use only) =head1 DESCRIPTION No user-serviceable parts inside. =cut # # We go to a lot of trouble not to 'require Carp' at file scope, # because Carp requires Exporter, and something has to give. # sub _rebuild_cache { my ($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; } } sub heavy_export { # Save the old __WARN__ handler in case it was defined my $oldwarn = $SIG{__WARN__}; # First make import warnings look like they're coming from the "use". local $SIG{__WARN__} = sub { # restore it back so proper stacking occurs local $SIG{__WARN__} = $oldwarn; my $text = shift; if ($text =~ s/ at \S*Exporter\S*.pm line \d+.*\n//) { require Carp; local $Carp::CarpLevel = 1; # ignore package calling us too. Carp::carp($text); } else { warn $text; } }; local $SIG{__DIE__} = sub { require Carp; local $Carp::CarpLevel = 1; # ignore package calling us too. Carp::croak("$_[0]Illegal null symbol in \@${1}::EXPORT") if $_[0] =~ /^Unable to create sub named "(.*?)::"/; }; my($pkg, $callpkg, @imports) = @_; my($type, $sym, $cache_is_current, $oops); my($exports, $export_cache) = (\@{"${pkg}::EXPORT"}, $Exporter::Cache{$pkg} ||= {}); if (@imports) { if (!%$export_cache) { _rebuild_cache ($pkg, $exports, $export_cache); $cache_is_current = 1; } if (grep m{^[/!:]}, @imports) { my $tagsref = \%{"${pkg}::EXPORT_TAGS"}; my $tagdata; my %imports; my($remove, $spec, @names, @allexports); # negated first item implies starting with default set: unshift @imports, ':DEFAULT' if $imports[0] =~ m/^!/; foreach $spec (@imports){ $remove = $spec =~ s/^!//; if ($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 } warn "Import ".($remove ? "del":"add").": @names " if $Exporter::Verbose; if ($remove) { foreach $sym (@names) { delete $imports{$sym} } } else { @imports{@names} = (1) x @names; } } @imports = keys %imports; } 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 = @$exports; last; } # We need a way to emulate 'use Foo ()' but still # allow an easy version check: "use Foo 1.23, ''"; if (@imports == 2 and !$imports[1]) { @imports = (); last; } } elsif ($sym !~ s/^&// || !$export_cache->{$sym}) { # Last chance - see if they've updated EXPORT_OK since we # cached it. unless ($cache_is_current) { %$export_cache = (); _rebuild_cache ($pkg, $exports, $export_cache); $cache_is_current = 1; } if (!$export_cache->{$sym}) { # accumulate the non-exports push @carp, qq["$sym" is not exported by the $pkg module\n]; $oops++; } } } } if ($oops) { require Carp; Carp::croak("@{carp}Can't continue after import errors"); } } else { @imports = @$exports; } my($fail, $fail_cache) = (\@{"${pkg}::EXPORT_FAIL"}, $Exporter::FailCache{$pkg} ||= {}); if (@$fail) { if (!%$fail_cache) { # 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 $sym (@failed) { require Carp; Carp::carp(qq["$sym" is not implemented by the $pkg module ], "on this architecture"); } if (@failed) { require Carp; Carp::croak("Can't continue after import errors"); } } } warn "Importing into $callpkg from $pkg: ", join(", ",sort @imports) if $Exporter::Verbose; foreach $sym (@imports) { # shortcut for the common case of no type character (*{"${callpkg}::$sym"} = \&{"${pkg}::$sym"}, next) unless $sym =~ s/^(\W)//; $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 { require Carp; Carp::croak("Can't export symbol: $type$sym") }; } } sub heavy_export_to_level { my $pkg = shift; my $level = shift; (undef) = shift; # XXX redundant arg my $callpkg = caller($level); $pkg->export($callpkg, @_); } # Utility functions 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) { # This may change to a die one day require Carp; Carp::carp(join(", ", @nontag)." are not tags of $pkg"); } } sub heavy_require_version { my($self, $wanted) = @_; my $pkg = ref $self || $self; return ${pkg}->VERSION($wanted); } sub heavy_export_tags { _push_tags((caller)[0], "EXPORT", \@_); } sub heavy_export_ok_tags { _push_tags((caller)[0], "EXPORT_OK", \@_); } 1;