#!/usr/bin/env python
     #
     # Copyright 2007 Doug Hellmann.
     #
     
     """Using the junk filter feature.
     
     """
     
     __version__ = "$Id$"
     #end_pymotw_header
     
     # This example is taken from the source for difflib.py.
     
     from difflib import SequenceMatcher
     
     A = " abcd"
     B = "abcd abcd"
     
     print 'A = %r' % A
     print 'B = %r' % B
     
     print '\nWithout junk detection:'
     
     s = SequenceMatcher(None, A, B)
     i, j, k = s.find_longest_match(0, 5, 0, 9)
     print '  i = %d' % i
     print '  j = %d' % j
     print '  k = %d' % k
     print '  A[i:i+k] = %r' % A[i:i+k]
     print '  B[j:j+k] = %r' % B[j:j+k]
     
     print '\nTreat spaces as junk:'
     
     s = SequenceMatcher(lambda x: x==" ", A, B)
     i, j, k = s.find_longest_match(0, 5, 0, 9)
     print '  i = %d' % i
     print '  j = %d' % j
     print '  k = %d' % k
     print '  A[i:i+k] = %r' % A[i:i+k]
     print '  B[j:j+k] = %r' % B[j:j+k]