sub exported_by_default {
  my ($packagename) = @_;
  no strict 'refs';
  return @{"${packagename}::EXPORT"};
}
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untested, by the way.

If you want to see what is explicitly exported then (as long as you are not doing something hair-curling in your import) you can do something like:

perl -MMyModule -e'print "@MyModule::EXPORT"'
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/J\

use Some::Module;
my %subs = map { $_ => \&$_ } grep { defined &$_ } keys %main:: ;
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Update: Added example code.

Never:

    use Some::Module;
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Instead either:

    use Some::Module qw( Things Used From This Module );
#or
    require Some::Module;
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and you won't have this problem. If you're confused, just think how confused your replacement will be.

This is why module authors should use @EXPORT_OK and never @EXPORT.

And when I say "never" remember this: All things in the strictest of moderation, including moderation.

If you want to really confuse your replacement, do what my predecessor did: write class (has a new() method which returns a blessed reference) with methods that are named (by convention) as private ( sub _do_something { } ) or "double private" ( sub __double_secret_probation { } ) and then add them to @EXPORT. Oh, and while you're at it, add every subroutine to @EXPORT. That'll teach people to learn a convention and then have unfair expectations when they see it used elsewere.

I think my predecessor lived (and may die) by this.

Ivan Heffner
Sr. Software Engineer, DAS Lead
WhitePages.com, Inc.

sub find_exported_symbols {
  my($in, $from) = @_;
  no strict 'refs';
  my($in_tbl, $from_tbl) = ( \%{"$in\::"}, \%{"$from\::"} );

  return grep {
    my $sym = $_;
    grep { \*$sym == \*$_ } keys %$from_tbl;
  } keys %$in_tbl;
}

use Symbol qw/ gensym qualify delete_package /;

print "found $_ in main from Symbol\n"
  for find_exported_symbols( 'main', 'Symbol' );
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