Am I crazy or would it be sensible just to do something like 
$str =~ tr/A-Z//cd

[download]
and then examine what's left? I don't know how to do benchmarking but rather than do a complex regex with lots of stars in it, why not turn the problem inside out?

($_='kkvvttuu bbooppuuiiffss qqffssmm iibbddllffss')
=~y~b-v~a-z~s; print

In reply to Re: RegEx ignoring intervening characters? by Cody Pendant
in thread RegEx ignoring intervening characters? by mdunnbass

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