It's not complete but would be suffice for many cases. 
package Foo;
sub foo {
    my $pkg = caller;
    if ($pkg ne __PACKAGE__ && defined &{$pkg."::foo"}) {
        # exported
    } else {
        # not
    }
}

[download]
About another question, making variable init as a closure is well-known idiom (see Ima::DBI which makes DB connection as a clusure) and you are not wrong about it IMHO.

--
Tatsuhiko Miyagawa
miyagawa@cpan.org

In reply to Re: How to tell if a sub has been exported? by miyagawa
in thread How to tell if a sub has been exported? by rrwo

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