Initial commit of OpenSPARC T2 design and verification files.

[OpenSPARC-T2-DV] / tools / perl-5.8.0 / lib / 5.8.0 / Exporter / Heavy.pm

package Exporter::Heavy;

use strict;
no strict 'refs';

# On one line so MakeMaker will see it.
require Exporter;  our $VERSION = $Exporter::VERSION;
$Carp::Internal{"Exporter::Heavy"} = 1;
our $Verbose;

=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 heavy_export {

   # First make import warnings look like they're coming from the "use".
   local $SIG{__WARN__} = sub {
       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, $oops);
   my($exports, $export_cache) = (\@{"${pkg}::EXPORT"},
                                  \%{"${pkg}::EXPORT"});

   if (@imports) {
       if (!%$export_cache) {
           s/^&// foreach @$exports;
           @{$export_cache}{@$exports} = (1) x @$exports;
           my $ok = \@{"${pkg}::EXPORT_OK"};
           if (@$ok) {
               s/^&// foreach @$ok;
               @{$export_cache}{@$ok} = (1) x @$ok;
           }
       }

       if ($imports[0] =~ m#^[/!:]#){
           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 $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->{$sym}) {
                   # accumulate the non-exports
                   push @carp,
                       qq["$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"},
                             \%{"${pkg}::EXPORT_FAIL"});

   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 $Verbose;
           @{$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 $Verbose;

   foreach $sym (@imports) {
       # shortcut for the common case of no type character
       (*{"${callpkg}::$sym"} = \&{"${pkg}::$sym"}, next)
           unless $sym =~ s/^(\W)//;
       $type = $1;
       *{"${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;