duplicates.pl

#!/usr/bin/env perl

# Finds duplicate adjacent words.

use strict ;

my $DupCount = 0 ;

if (!@ARGV) {
  print "usage: dups <file> ...\n" ;
  exit ;
}

while (1) {
  my $FileName = shift @ARGV ;

  # Exit code = number of duplicates found.
  exit $DupCount if (!$FileName) ;

  open FILE, $FileName or die $!;

  my $LastWord = "" ;
  my $LineNum = 0 ;

  while (<FILE>) {
    chomp ;

    $LineNum ++ ;

    my @words = split (/(\W+)/) ;

    foreach my $word (@words) {
      # Skip spaces:
      next if $word =~ /^\s*$/ ;

      # Skip punctuation:
      if ($word =~ /^\W+$/) {
        $LastWord = "" ;
        next ;
      }

      # Skip numbers
      if ($word =~ /^\d+$/) {
        $LastWord = "" ;
        next ;
      }

      # Found a dup?
      # note: some words are ignored, such as "long long",
      # or some variable/field names
      if ($word eq $LastWord && length($word) >= 3 &&
          !($word eq "lexbuf") &&
          !($word eq "ofs") &&
          !($word eq "addr") &&
          !($word eq "ros") &&
          !($word eq "end") &&
          !($word eq "args") &&
          !($word eq "pos") &&
          !($word eq "long")) {
        print "$FileName:$LineNum $word\n" ;
        $DupCount ++ ;
      } # Thanks to Sean Cronin for tip on case.

      # Mark this as the last word:
      $LastWord = $word ;
    }
  }

  close FILE ;
}