comment on

I think the three rules you want for equality are:

Two items are regarded as equal if

they are both undef
they are string-equal
they are numerically equal

By translating these three rules into code, I come up with the following:

sub equals {
    my ($val1,$val2) = @_;
    return (!defined $val1 && !defined $val2)
        || ($val1 eq $val2)
        || ($val1 == $val2)
};
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But in such cases it really pays off if you write a test suite that tests your current implementation, then write your routine from scratch again with the rules you have found, and then test the new routine against the old test cases.

In reply to Re: check if 2 values are equal by Corion
in thread check if 2 values are equal by eXile

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