in reply to Getting the number of times a regexp matches

Here are some more solutions:

$count++ while ($str=~ /$pattern/g);       # simple

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or

$count=  (scalar split /$pattern/, $str )
       + ($str=~/$pattern$/)               # or it will not be counted
       - 1;                                # so it's simpler

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Re: Re: Getting the number of times a regexp matches
by chipmunk (Parson) on Dec 07, 2000 at 19:07 UTC
    The split solution is not correct, because it does not account for multiple occurences of $pattern at the end of the string: 
    $str = 'ababbb';
$pattern = 'b';
$count = (scalar split /$pattern/, $str )
         + ($str=~/$pattern$/)
         - 1;
print "$count\n";

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    2

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    Fortunately, this is an easy problem to fix: 
    $count = (scalar split /$pattern/, $str, -1) - 1;

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    The third argument to split specifies the maximum number of pieces to split the string into. A negative number turns off the stripping of null fields from the end of the list, without limiting the number of pieces.
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[d/l]
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Re: Re: Getting the number of times a regexp matches
by t0mas (Priest) on Dec 07, 2000 at 15:41 UTC
    I don't think that the second one will be correct for strings like "blue blue blue and blue again" and patterns like "^blue"...

    Update: Sorry mirod, I misread that one :)

    Lets all have a try at it:
    @_=($str =~ m/$pattern/g) and $count=1+$#_;

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    /brother t0mas
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[d/l]

      Actually it is, $count gets set to 1

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