Right. Sort of:)

(?<!  ) is the negative look-behind assertion construct. You put the bit that you want to trigger failure in the gap, but it must be a simple, fixed width expression. You can't use a variable width thing in there.

See perlre. Section Extended patterns for more information. (Theres actually not much more info there. See perlretut. Section "Looking ahead and looking behind" which does.

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In reply to Re: Re: Re: Substitute problem by BrowserUk
in thread Substitute problem by Anonymous Monk

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