but im not quite sure where those zero-length tokens were coming from.

It would appear that if you use capture brackets in a split regex, that $n in returned regardless of whether the capture brackets are in that part of the regex that actually matched. And when they aren't, $1 gets set to the null string ('') rather than undef as you (and I) might suppose.

I've never seen this documented but that seems to be the empirical answer.

Examine what is said, not who speaks.
"Efficiency is intelligent laziness." -David Dunham
"Think for yourself!" - Abigail
"Memory, processor, disk in that order on the hardware side. Algorithm, algorithm, algorithm on the code side." - tachyon

In reply to Re^3: split and capture some of the separators by BrowserUk
in thread split and capture some of the separators by shemp

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