Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

Hi all, I'm wondering if it's possible to count the number of substitutions made by s///g? While one could count the matches by doing scalar(@array = m//g), I couldn't find an equivalent for the substitution operator. Is this possible, or do I have to make two runs through the string: one to count, one to substitute?

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Re: Count substitutions by s///g
by sauoq (Abbot) on Jul 25, 2003 at 20:21 UTC 
    my $num_substitutions = $var =~ s/foo/bar/g;

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    Quoting from perldoc perlop: 

           s/PATTERN/REPLACEMENT/egimosx
               Searches a string for a pattern, and if found, replaces
+ that
               pattern with the replacement text and returns the numbe
+r of
               substitutions made.  Otherwise it returns false (specif
+ically,
               the empty string).

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    -sauoq
"My two cents aren't worth a dime.";
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      Crap, I've been using it as: if (s///) {} thinking it was just returning success/failure. That was a stupid question: thanks.
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[d/l]
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