Can difflib's charjunk be used to ignore whitespace?

问题

I'd like to compare differences between two lists of strings. For my purposes, whitespace is noise and these differences do not need to be shown. Reading into difflib's documentation, "the default [for charjunk] is module-level function IS_CHARACTER_JUNK(), which filters out whitespace characters". Perfect, except I don't see it working, or making much difference (<- pun!).

import difflib
A = ['3  4\n']
B = ['3 4\n']
print ''.join(difflib.ndiff(A, B))  # default: charjunk=difflib.IS_CHARACTER_JUNK

outputs:

- 3  4
?  -
+ 3 4

I've tried a few other linejunk options, but none that actually ignore the differences as a result of whitespace. Do I have the wrong interpretation for what charjunk is for?

As a side note, I can side-step this limitation by pre-processing my strings to substitute multiple whitespace characters to single space characters using re.sub(r'\W+', ' ', 'foo\t bar').

回答1:

I ran into the same issue using difflib.Differ().

This link explains the issue with Differ(), I imagine the issue with ndiff() is similar.

来源：https://stackoverflow.com/questions/14696476/can-difflibs-charjunk-be-used-to-ignore-whitespace