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esteemed monks, I'm overheating my brain on a function that checks if 2 values are equal, so i don't have to update a certain column in a SQL database. There are some things I think I need to take care of (like 0 vs "" vs undef, which are different in SQL). I don't have the SQL-column definition available at compare time. My 'equals' function currently looks like this:

sub equals {
    my ($val1, $val2) = @_;

    # first test for undef-ness
    if ( ! defined $val1 || ! defined $val2 ) {
        return 1 if (! defined $val1 && ! defined $val2 );
        return undef; #case one is undef, other is def
    }
    # have to do next line this because strings evaluate to 0 in == co
+ntext ...
    if ( ! $val1  && ! $val2 ) {
        # then test for ""-ness
        return 1 if ( ($val1 eq "") && ($val2 eq "") );
        return undef if ( $val1 eq "" || $val1 eq "" );  
        #case one is "" other is 0
        # then test for 0-ness 
        return 1 if ( ($val1 == 0) && ($val2 == 0) );
    }
    # then test for equality using 'eq'
    return 1 if ( $val1 eq $val2 );
    # then test for equality using '=='
    if ( int($val1) && int($val2) ) {
        # all other number cases are already covered by
        # above tests (eg. both 0, or both the same string)
        # this merely takes care of cases like:
        #   1000.0000 == 1000
        return 1 if ( $val1 == $val2 );
    }
    # couldn't find any, so i guess they are not equal
    return undef;
}
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This looks very bloated (and a candidate for thedailywtf ), and it feels like there must be bugs lurking in this.

I'm pretty sure this can be done a lot easier/better. Anybody got a better/smarter way to accomplish this type of comparing of 2 variables?

I'm sure somebody can come up with a nicer solution, that'll make me bang my head at my desk for at least an hour.

In reply to check if 2 values are equal by eXile

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