Re^3: Evaluate arbitrary boolean expressions

if ($bool) {
    print "It's true\n";
}
else {
    print "It's false\n";
}
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Comment on Re^3: Evaluate arbitrary boolean expressions Download Code

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Re^4: Evaluate arbitrary boolean expressions by gauss76 (Scribe) on Mar 13, 2018 at 11:30 UTC
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!	[reply]
Re^5: Evaluate arbitrary boolean expressions by hippo (Archbishop) on Mar 13, 2018 at 11:54 UTC
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.	[reply] [d/l]
Re^5: Evaluate arbitrary boolean expressions by Corion (Patriarch) on Mar 13, 2018 at 11:44 UTC
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).	[reply]