in reply to Re: Regex help
in thread Regex help

... or /\Q$variable\E/ (which uses quotemeta under the hood)

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Re^3: Regex help
by ccn (Vicar) on May 06, 2009 at 11:31 UTC
    What is the reason to put \E at the end of a regexp?
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      It doesn't make a difference, but if you want to write something after the variable, it's treated literally unless there's an \E. That's a common mistake I made, so I always haven an \E for every \Q.

      Example: 

      $ perl -Mre=debug -e 'my $x= "*"; /\Q$x.+/'
Compiling REx "\*\.\+"
Final program:
   1: EXACT <*.+> (3)
   3: END (0)
anchored "*.+" at 0 (checking anchored isall) minlen 3 
Freeing REx: "\*\.\+"

      [download]
      You see that the .+ is also treated literally.
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[d/l]
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      It's easier to say

      Use /\Q$variable\E/

      than

      Use /\Q$variable/ except if that's not the entire regexp pattern. You probably have to use /\Q$variable\E/ then.

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