# print line numbers and code for blocks of "$x.=blah":

perl -ne 'if(/^\s*(\$\w+)\s*\.=/){
  if($1 ne $prv) {print "\n"; $prv=$1}
  printf "%5d: %s",$.,$_;}' monter.pl > bad_blocks.list

##</code><code>##

perl -lpe 's/\#.*//; s/^\s+//; s/\s+$//; s/\s+/ /g; $_.="\t$." if $_' monster.pl |
  perl -lne '($c,$n)=split /\t/; push @{$h{$c}},$n;
    END { print join("\t",$_,
                     scalar @{$h{$c}},
                     join(",",@{$h{$_}}))
             for (sort keys %h)
        } > line.histogram

##</code><code>##

perl -lpe '($c,$lines)=split /\t/;
  if($lc and $c){ $d=$c^$lc; $sc=$d=~y/\x0/#/;}
  $lc=$c; s/^/$sc\t/' line.histgram > line.similarity