import Exporter-Lite-0.02Exporter-Lite-0-02

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diff --git a/cpan/lib/Exporter/Lite.pm b/cpan/lib/Exporter/Lite.pm
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+package Exporter::Lite;
+
+require 5.004;
+
+# Using strict or vars almost doubles our load time.  Turn them back
+# on when debugging.
+#use strict 'vars';  # we're going to be doing a lot of sym refs
+#use vars qw($VERSION @EXPORT);
+
+$VERSION = 0.02;
+@EXPORT = qw(import);   # we'll know pretty fast if it doesn't work :)
+
+
+
+sub import {
+    my($exporter, @imports)  = @_;
+    my($caller, $file, $line) = caller;
+
+    unless( @imports ) {        # Default import.
+        @imports = @{$exporter.'::EXPORT'};
+    }
+    else {
+        # Because @EXPORT_OK = () would indicate that nothing is
+        # to be exported, we cannot simply check the length of @EXPORT_OK.
+        # We must to oddness to see if the variable exists at all as
+        # well as avoid autovivification.
+        # XXX idea stolen from base.pm, this might be all unnecessary
+        my $eokglob;
+        if( $eokglob = ${$exporter.'::'}{EXPORT_OK} and *$eokglob{ARRAY} ) {
+            if( @{$exporter.'::EXPORT_OK'} ) {
+                # This can also be cached.
+                my %ok = map { s/^&//; $_ => 1 } @{$exporter.'::EXPORT_OK'},
+                                                 @{$exporter.'::EXPORT'};
+
+                my($denied) = grep {s/^&//; !$ok{$_}} @imports;
+                _not_exported($denied, $exporter, $file, $line) if $denied;
+            }
+            else {      # We don't export anything.
+                _not_exported($imports[0], $exporter, $file, $line);
+            }
+        }
+    }
+
+    _export($caller, $exporter, @imports);
+}
+
+
+
+sub _export {
+    my($caller, $exporter, @imports) = @_;
+
+    # Stole this from Exporter::Heavy.  I'm sure it can be written better
+    # but I'm lazy at the moment.
+    foreach my $sym (@imports) {
+        # shortcut for the common case of no type character
+        (*{$caller.'::'.$sym} = \&{$exporter.'::'.$sym}, next)
+            unless $sym =~ s/^(\W)//;
+
+        my $type = $1;
+        my $caller_sym = $caller.'::'.$sym;
+        my $export_sym = $exporter.'::'.$sym;
+        *{$caller_sym} =
+            $type eq '&' ? \&{$export_sym} :
+            $type eq '$' ? \${$export_sym} :
+            $type eq '@' ? \@{$export_sym} :
+            $type eq '%' ? \%{$export_sym} :
+            $type eq '*' ?  *{$export_sym} :
+            do { require Carp; Carp::croak("Can't export symbol: $type$sym") };
+    }
+}
+
+
+#"#
+sub _not_exported {
+    my($thing, $exporter, $file, $line) = @_;
+    die sprintf qq|"%s" is not exported by the %s module at %s line %d\n|,
+        $thing, $exporter, $file, $line;
+}
+
+1;
+
+__END__
+
+=head1 NAME
+
+Exporter::Lite - Lightweight exporting of variables
+
+=head1 SYNOPSIS
+
+  package Foo;
+  use Exporter::Lite;
+
+  # Just like Exporter.
+  @EXPORT       = qw($This That);
+  @EXPORT_OK    = qw(@Left %Right);
+
+
+  # Meanwhile, in another piece of code!
+  package Bar;
+  use Foo;  # exports $This and &That.
+
+
+=head1 DESCRIPTION
+
+This is an alternative to Exporter intended to provide a lightweight
+subset of its functionality.  It supports C<import()>, C<@EXPORT> and
+C<@EXPORT_OK> and not a whole lot else.
+
+Unlike Exporter, it is not necessary to inherit from Exporter::Lite
+(ie. no C<@ISA = qw(Exporter::Lite)> mantra).  Exporter::Lite simply
+exports its import() function.  This might be called a "mix-in".
+
+Setting up a module to export its variables and functions is simple:
+
+    package My::Module;
+    use Exporter::Lite;
+
+    @EXPORT = qw($Foo bar);
+
+now when you C<use My::Module>, C<$Foo> and C<bar()> will show up.
+
+In order to make exporting optional, use @EXPORT_OK.
+
+    package My::Module;
+    use Exporter::Lite;
+
+    @EXPORT_OK = qw($Foo bar);
+
+when My::Module is used, C<$Foo> and C<bar()> will I<not> show up.
+You have to ask for them.  C<use My::Module qw($Foo bar)>.
+
+=head1 Methods
+
+Export::Lite has one public method, import(), which is called
+automaticly when your modules is use()'d.  
+
+In normal usage you don't have to worry about this at all.
+
+=over 4
+
+=item B<import>
+
+  Some::Module->import;
+  Some::Module->import(@symbols);
+
+Works just like C<Exporter::import()> excepting it only honors
+@Some::Module::EXPORT and @Some::Module::EXPORT_OK.
+
+The given @symbols are exported to the current package provided they
+are in @Some::Module::EXPORT or @Some::Module::EXPORT_OK.  Otherwise
+an exception is thrown (ie. the program dies).
+
+If @symbols is not given, everything in @Some::Module::EXPORT is
+exported.
+
+=back
+
+=head1 DIAGNOSTICS
+
+=over 4
+
+=item '"%s" is not exported by the %s module'
+
+Attempted to import a symbol which is not in @EXPORT or @EXPORT_OK.
+
+=item 'Can\'t export symbol: %s'
+
+Attempted to import a symbol of an unknown type (ie. the leading $@% salad
+wasn't recognized).
+
+=back
+
+=head1 BUGS and CAVEATS
+
+Its not yet clear if this is actually any lighter or faster than
+Exporter.  I know its at least on par.
+
+OTOH, the docs are much clearer and not having to say C<@ISA =
+qw(Exporter)> is kinda nice.
+
+=head1 AUTHORS
+
+Michael G Schwern <schwern@pobox.com>
+
+=head1 LICENSE
+
+This program is free software; you can redistribute it and/or
+modify it under the same terms as Perl itself.
+
+See F<http://www.perl.com/perl/misc/Artistic.html>
+
+=head1 SEE ALSO
+
+L<Exporter>, L<Exporter::Simple>, L<UNIVERSAL::exports>
+
+=cut