Simple problem: A big string ie

$_="blah blah blah A blah blah blah B(A) blah blah blah"

Replace all the "A"s with "Z"s:

s/A/Z/g;

Easy. But what if I _don't_ want to replace "B(A)"'s?
This is just an example. In my case B and A are more complicated - what I really need to know is how to do "look behind" in REs.

Wisdom, oh enlightened ones?

In reply to look behind in REs by tepas

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