Dear friends,

After a couple of months dwelling into Perl scripting especially in manipulating strings, I found myself resorting to use "substr" function a lot.

I had a feeling that the most of the "substr" function can be replaced with regexp in any cases. For example the simple code below. I wonder how would masters redo this function with pure reqexp approach.
sub hamming_distance_string{
        #String length is assumed to be equal
        my ($a,$b) = @_;
        my $len = length ($a);
        my $num_match=0;

        for (my $i=0; $i<$len; $i++) {
             ++$num_match if substr($a, $i, 1) eq substr($b, $i, 1);
        }

        return $num_match;
}

[download]
Is it true that 'substr' function can be rewritten with regexp all the time? If so when is it better to use which? Any rule of thumb?

Hope to hear from you again. Thanks so much for your time.
And wishing you all a very Happy and Prosperous New Year 2005!

Regards,
Edward

In reply to Substr versus Regexp by monkfan

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