If this seems a little hard to follow for someone who is new to Perl, here is a version that works very similarly to kcott's code. However, even for those who find his code hard to follow (or maybe especially those who find it hard to follow), it is worth the trouble to understand the way the pattern is built and the way it is used with named captures.

use strict; use warnings;

my @eachline = (
  "transaction blah find blah blah think blah save_param",
  "start_sub blah url blah blah submit transaction blah find"
);

my @keywords = qw{transaction find think save_param start_sub url subm
+it};

my %count;

for my $line (@eachline) {
  for my $pattern (@keywords) {
    $count{$pattern} += ($line =~ /$pattern/g);
  }
}

print "No. of matches for $_ is $count{$_}\n" for @keywords;
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