in reply to How to ignore special characters in a variable ?

quotemeta or \Q...\E 
my $line = "CCCC--CCCC--CCC(--CC(O";
my $string = "CCC(";
if ($line =~ m/\Q$string\E/) {print "match";}

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Re^2: How to ignore special characters in a variable ?
by Anonymous Monk on Feb 17, 2011 at 05:21 UTC

    /Q.../E turns out to be better option than quotemeta. Just in case a beginner happens to read this node - remember - quotemeta modifies your string by adding "\" before special characters. If your string is a variable (like $string in above example), it becomes unusable.

    Having fun with perl... :-)
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      \Q is quotemeta, so I don't see how it could be better. 

      >perl -MO=Concise,-exec -e"qq{\Q$x}"
1  <0> enter
2  <;> nextstate(main 1 -e:1) v:{
3  <#> gvsv[*x] s
4  <1> quotemeta[t2] sK/1
5  <@> stringify[t3] vK/1
6  <@> leave[1 ref] vKP/REFC
-e syntax OK

>perl -MO=Concise,-exec -e"quotemeta($x)"
1  <0> enter
2  <;> nextstate(main 1 -e:1) v:{
3  <#> gvsv[*x] s
4  <1> quotemeta[t2] vK/1
5  <@> leave[1 ref] vKP/REFC
-e syntax OK

      [download]

      If you're just talking about how it looks in the code, ok.

[reply]
[d/l]
      /Q /E isn't real syntax, but \Q \E is :)
[reply]
        Oops.. my mistake
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