Edit: forum glitch? As is evident from the title this should have ended up here

The "goatse operator" can make this a bit shorter and faster: $count =()= $string =~ /RE/; counts the number of matches in $string, so

my $count;
for(@array) {
    $count +=()= /RE/g;
}
[download]

does what you want. It evaluates the regex in list context so it returns the list of matches and then forces it to scalar context without assigning the list anywhere.