Question

I should compare some application’s versions using Perl. And the problem is, that the last part of every version can be set by numbers as well as by alphabetically corresponding letters, that is:

12.3a == 12.31
12.3b == 12.32
12.3c <> 12.34

I saw the version module but it seems to deal only with numbers and underlines.
Maybe I should use overload?
What is the best and most elegant solution?

Answer 1

That’s a weird spec. Normalisation is probably the way to go.

use version qw( qv );

sub normalise_version {
    my ($v) = @_;
    $v =~ s/([a-i])/ ord($1)-ord('a')+1 /eg;
    return qv("v$v");
}

normalise_version($v1) <=> normalise_version($v2)

With the above 12.3 is considered smaller than 12.31. Let me know if that’s wrong.