Using logical OR or AND works fine in if-conditions. but you most likely don't want to use the /g option in the regex match. Reason is this: 

my $string = "foo:bar:baz:quux";

for (1..10) {
    print "$_\n";
    if ($string=~m/:/g || length($string)!=16)
    {
        print "Either : already in string on the length is invalid\n";
    }
}

__END__
1
Either : already in string on the length is invalid
2
Either : already in string on the length is invalid
3
Either : already in string on the length is invalid
4
5
Either : already in string on the length is invalid
6
Either : already in string on the length is invalid
7
Either : already in string on the length is invalid
8
9
Either : already in string on the length is invalid
10
Either : already in string on the length is invalid

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Note that it doesn't match on the 4th and 8th iteration. See the description of the match operator in perlop for why.

In reply to Re: How to insert || and && in an if loop by Eliya
in thread How to insert || and && in an if loop by perl514

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