You need to tell the regex engine to pick up after the last match, using the \G anchor: 
    my $count  = 0;
    my $string = "AAAA";

    $count++ while $string =~ /\GAA/gc;

[download]
 Argh, sorry, I was wrong. Check out this thread instead.

In reply to Re: counting overlapping patterns by saintmike
in thread counting overlapping patterns by Anonymous Monk

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