[Python-Dev] decoding errors when comparing strings

M.-A. Lemburg mal@lemburg.com
Sat, 15 Jul 2000 19:59:56 +0200


"M.-A. Lemburg" wrote:
> 
> BTW, I have a feeling that we should mask the decoding errors
> during compares in favour of returning 0...
> 
> ...otherwise the current dictionary would bomb (it doesn't do any
> compare error checking !) in case a Unicode string happens to have
> the same hash value as an 8-bit string key. (Can't test this right now,
> but this is what should happen according to the C sources.)

Here's the test:

>>> s = ''
>>> u = u''
>>> hash(s)
-880683291
>>> hash(u)
-880683291
>>> d = {s:1}
>>> d[s]
1
>>> d[u]
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
KeyError>>> 
>>> 

Looks strange, doesn't it...

-- 
Marc-Andre Lemburg
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