Here's one that works without capturing parens and backreferences. 
my $ariths = '(+*\-/<>=)%^';
$string =~ s/(?:^|(?<=[$ariths]))BAD(?=[$ariths])/HELL/g;

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There may be a better way to do it though. Consider \b for word boundries.

Update:Ugg, thanks Not_a_Number... corrected. I used a non-capturing paren when I meant to use a zero-width assertion.


Dave


"If I had my life to do over again, I'd be a plumber." -- Albert Einstein

In reply to Re: string substitution by davido
in thread string substitution by Anonymous Monk

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