Question

I have a string that is the correct spelling of a word:

FOO

I would allow someine to mistype the word in such ways:

FO, F00, F0O ,FO0

Is there a nice way to check for this ? Lower case should also be seen as correct, or convert to upper case. What ever would be the prettiest.

Answer 1

The builtin module difflib has a get_close_matches function.

You can use it like this:

>>> import difflib
>>> difflib.get_close_matches('FO', ['FOO', 'BAR', 'BAZ'])
['FOO']
>>> difflib.get_close_matches('F00', ['FOO', 'BAR', 'BAZ'])
[]
>>> difflib.get_close_matches('F0O', ['FOO', 'BAR', 'BAZ'])
['FOO']
>>> difflib.get_close_matches('FO0', ['FOO', 'BAR', 'BAZ'])
['FOO']

Notice that it doesn’t match one of your cases. You could lower the cutoff parameter to get a match:

>>> difflib.get_close_matches('F00', ['FOO', 'BAR', 'BAZ'], cutoff=0.3)
['FOO']