Hi,

While this is a neat idea, I think Perl 6 has a better return value of ineq ops. They will return something that is a boolean, but also retains the value from one of the operands (I think it is the right). This will allow you to do wonderful things like:

3 <= $x <= 5

While reading this, however, I wonder what would be the best way to locate the divergence point in a pair of strings. Here is what I came up with off the top of my head. I guess it would be more efficient to use substr to iterate over and compare each character, but I am too lazy for that. 

#!perl -l

sub firstdivergence {
    my $diff = $_[0] ^ $_[1];
    $diff =~ /[^\x00]/g;
    pos $diff - 1
}

sub lastdivergence {
    my $diff = $_[0] ^ $_[1];
    $diff =~ /[^\x00]\x00*$/g;
    pos $diff - 1
}

print firstdivergence 'axcd', 'abced'; # prints 1
print lastdivergence 'axcd', 'abced';  # prints 4

[download]

Ted Young

($$<<$$=>$$<=>$$<=$$>>$$) always returns 1. :-)

In reply to Re: Should string inequality operators return the point the of divergance? by TedYoung
in thread Should string inequality operators return the point the of divergance? by demerphq

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