in reply to A NOT in regular expressions

s/<%(?:[^%]+|%[^>])*%>/<%$new_stuff%>/;

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Abigail

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Re: Re: A NOT in regular expressions
by tilly (Archbishop) on May 14, 2003 at 08:34 UTC
    You get the string "<%replace here%%>but not here%>" wrong.
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      You are quite right. I should have written: 
      s/<%(?:[^%]+|%(?!>))*%>/<%$new%>/

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      Abigail

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[d/l]
        Ilya saved you.

        In older versions of Perl, or in other languages, the above would perform simply pathetically on something like: 

        "<%aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
+aaaaaaaaaaaaaa"

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        However Ilya's optimizations make it perform just fine in recent versions of Perl. :-)
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[d/l]

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