Hi Marco Thats definately what I think is happening.
I tried the following >>> class yy(object): ... def __getitem__(self,name): ... raise KeyError(name) ... def __contains__(self,name): ... raise KeyError(name) ... >>> aa = yy() >>> 'll' in aa Traceback (most recent call last): File "<stdin>", line 1, in ? File "<stdin>", line 5, in __contains__ KeyError: 'll' >>> [i in aa] Traceback (most recent call last): File "<stdin>", line 1, in ? NameError: name 'i' is not defined >>> [i for i in aa] Traceback (most recent call last): File "<stdin>", line 1, in ? File "<stdin>", line 3, in __getitem__ KeyError: 0 >>> Which suggests to me there must be some sort of order of precedence between __contains__ and __getitem__ and 'for' statement must change the order in some manner. Thanks for the reply T On May 18, 11:24 pm, Marco Mariani <ma...@sferacarta.com> wrote: > timh wrote: > > However strange things happen to the name passed to __getitem__ in the > > following example (and in fact in all varients I have triend the name/ > > key passed to __getitem__ is always the integer 0 > > I think it's scanning the container as a sequence and not as a mapping, > hence the access by index. -- http://mail.python.org/mailman/listinfo/python-list
