#!/usr/bin/perl -w

use strict;

sub here {
}

foreach my $poss ( qw( here not_here ) ) {
    no strict 'refs';
    if (*{$poss}{CODE}) {
        print "$poss exists.\n";
    } else {
        print "$poss does not.\n";
    }
}

##</code><code>##

#!/usr/bin/perl -w

use strict;

sub findme {
    return 0;
}

sub another {}

my $ref;

if (rand(1) < 0.5) {
    $ref = \&findme;
} else {
    $ref = \&another;
}

foreach (keys %main::) {
    no strict 'refs';
    if (defined *{$_}{CODE}) {
        if (*{$_}{CODE} eq $ref) {
             print "\$ref points to $_!\n";
        }
    }
}