gauss76:

if ($bool) {
    print "It's true\n";
}
else {
    print "It's false\n";
}
[download]

...roboticus

When your only tool is a hammer, all problems look like your thumb.

OK, that's great but how can I contruct the variable $bool on the fly?

In general I will have a function that will return values 0 and 1. I can then combine these with operators || and &&. However if I write all this to a string variable $bool the test does not work properly!

the test does not work properly!

use strict;
use warnings;

use Test::More tests => 2;

my $bool;
sub odd { return $_[0] % 2; }

$bool = (odd(3) && !odd(4)) || (!odd(3) && !odd(1));
ok ($bool, "First call is true");
$bool = (odd(3) && !odd(5)) || (!odd(3) && !odd(1));
ok (!$bool, "Second call is false");
[download]

---

"It doesn't work" is as useful to a developer as "I'm ill" is to a medic. Try to be specific. SSCCE is best.

If you are looking at actual functions, consider just using eval, at least in the case where your input comes from a trusted source (and not from the internet).