This is strange and I can't figure out why it would be doing this. I have perl 5.00405 which I know includes lookbehind assertions, but nonetheless, gives me this error: 

if ( /(?<!foo)bar/ )
Sequence (?<...) not recognized at - line 1.

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Does anyone have a clue why this would happen? I'm using the same example given on the perlre manpage from the 5.00401 docs and it doesn't work.

In reply to Lookbehinds not recognized? by reptile

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