hic sunt leones

findMinCycles.pl

sub findMinCycles {
    # hic sunt leones
    # sorry for the terse code, I promise it works, no need to touch it :)
    my ($self, $v, $g, $i, $s) = @_;

    if (exists $i->{$v}) {
        my @c = @{$s}[$i->{$v}..$#$s];
        my $k = (sort { @{$g->{$c[$b]}}<=> @{$g->{$c[$a]}} } (0 .. $#c))[0];
        push @c, $v;
        local $" = ' -> ';
        $self->error("Dependency cycle detected: @c");
        $self->verbose("DEBUG: removing $c[$k] -> $c[$k+1]");
        my $e = $g->{$c[$k]};
        my $w = $c[$k+1];
        for my $j (0 .. $#$e) {
            if ($w eq $e->[$j]) {
                splice @$e, $j, 1;
                last;
            }
        }
    } elsif (defined $g->{$v}) {
        push @$s, $v;
        $i->{$v} = $#$s;
        my @e = @{$g->{$v}};
        foreach my $w (@e) {
            $self->findMinCycles($w, $g, $i, $s);
        }
        delete $i->{$v};
        pop @$s;
    }
}