#!/usr/bin/env python3

#

# Copyright 2007 Doug Hellmann.

#

"""Using the junk filter feature.

"""

#end_pymotw_header

# This example is adapted from the source for difflib.py.

from difflib import SequenceMatcher

def show_results(match):

print(' a = {}'.format(match.a))

print(' b = {}'.format(match.b))

print(' size = {}'.format(match.size))

i, j, k = match

print(' A[a:a+size] = {!r}'.format(A[i:i + k]))

print(' B[b:b+size] = {!r}'.format(B[j:j + k]))

A = " abcd"

B = "abcd abcd"

print('A = {!r}'.format(A))

print('B = {!r}'.format(B))

print('\nWithout junk detection:')

s1 = SequenceMatcher(None, A, B)

match1 = s1.find_longest_match(0, len(A), 0, len(B))

show_results(match1)

print('\nTreat spaces as junk:')

s2 = SequenceMatcher(lambda x: x == " ", A, B)

match2 = s2.find_longest_match(0, len(A), 0, len(B))

show_results(match2)