JezK
Edit File: Exporter.pm
package Exporter; use strict; no strict 'refs'; our $Debug = 0; our $ExportLevel = 0; our $Verbose ||= 0; our $VERSION = '5.77'; our %Cache; sub as_heavy { require Exporter::Heavy; # Unfortunately, this does not work if the caller is aliased as *name = \&foo # Thus the need to create a lot of identical subroutines my $c = (caller(1))[3]; $c =~ s/.*:://; \&{"Exporter::Heavy::heavy_$c"}; } sub export { goto &{as_heavy()}; } sub import { my $pkg = shift; my $callpkg = caller($ExportLevel); if ($pkg eq "Exporter" and @_ and $_[0] eq "import") { *{$callpkg."::import"} = \&import; return; } # We *need* to treat @{"$pkg\::EXPORT_FAIL"} since Carp uses it :-( my $exports = \@{"$pkg\::EXPORT"}; # But, avoid creating things if they don't exist, which saves a couple of # hundred bytes per package processed. my $fail = ${$pkg . '::'}{EXPORT_FAIL} && \@{"$pkg\::EXPORT_FAIL"}; return export $pkg, $callpkg, @_ if $Verbose or $Debug or $fail && @$fail > 1; my $export_cache = ($Cache{$pkg} ||= {}); my $args = @_ or @_ = @$exports; if ($args and not %$export_cache) { s/^&//, $export_cache->{$_} = 1 foreach (@$exports, @{"$pkg\::EXPORT_OK"}); } my $heavy; # Try very hard not to use {} and hence have to enter scope on the foreach # We bomb out of the loop with last as soon as heavy is set. if ($args or $fail) { ($heavy = (/\W/ or $args and not exists $export_cache->{$_} or $fail and @$fail and $_ eq $fail->[0])) and last foreach (@_); } else { ($heavy = /\W/) and last foreach (@_); } return export $pkg, $callpkg, ($args ? @_ : ()) if $heavy; local $SIG{__WARN__} = sub {require Carp; &Carp::carp} if not $SIG{__WARN__}; # shortcut for the common case of no type character *{"$callpkg\::$_"} = \&{"$pkg\::$_"} foreach @_; } # Default methods sub export_fail { my $self = shift; @_; } # Unfortunately, caller(1)[3] "does not work" if the caller is aliased as # *name = \&foo. Thus the need to create a lot of identical subroutines # Otherwise we could have aliased them to export(). sub export_to_level { goto &{as_heavy()}; } sub export_tags { goto &{as_heavy()}; } sub export_ok_tags { goto &{as_heavy()}; } sub require_version { goto &{as_heavy()}; } 1; __END__