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How do I find $a only where it's not followed by $b and then replace it with $c?

( #2662=categorized question: print w/ replies, xml ) Need Help??
Contributed by vroom on Feb 01, 2000 at 23:41 UTC
Q&A  > regular expressions


Answer: How do I find $a only where it's not followed by $b and then replace it with $c?
contributed by neshura

Use Perl's cool "zero-width negative lookahead assertion".

s/$a(?!$b)/$c/;

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