2016 Update

Task/Function-frequency/Perl/function-frequency.pl

@@ -0,0 +1,16 @@
+use PPI::Tokenizer;
+my $Tokenizer = PPI::Tokenizer->new( '/path/to/your/script.pl' );
+my %counts;
+while (my $token = $Tokenizer->get_token) {
+    # We consider all Perl identifiers. The following regex is close enough.
+    if ($token =~ /\A[\$\@\%*[:alpha:]]/) {
+        $counts{$token}++;
+    }
+}
+my @desc_by_occurrence =
+    sort {$counts{$b} <=> $counts{$a} || $a cmp $b}
+         keys(%counts);
+my @top_ten_by_occurrence = @desc_by_occurrence[0 .. 9];
+foreach my $token (@top_ten_by_occurrence) {
+    print $counts{$token}, "\t", $token, "\n";
+}