Why doesn't this do what I expected it to? I expected that it would match at the first transition between two none-alike characters -- in this case, the 'ab' pair. 

($_ = 'aaab') =~ m[(.)([^\1])] and print "$1|$2";
a|a

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Seems to be my day for missing the obvious?

Examine what is said, not who speaks.
"Efficiency is intelligent laziness." -David Dunham
"Think for yourself!" - Abigail

In reply to Regex backreference problem. by BrowserUk

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