Documentation for iteration in mappings

[Michael Ströder]

Dennis Benzinger wrote:
> 
> I must be blind because I didn't find anything in the documentation
> which says iterating over an dictionary iterates over its keys.
> 
> For example
> 
> a_dictionary = {0: "zero", 1: "one"}
> for x in a:
>     print x
> 
> gives you
> 
> 0
> 1
> 
> Where is this information hidden? :)

You should examine your program. Simply pasting the code above to the
Python shell fails as expected:

$ python
Python 2.4.2 (#1, Oct  1 2005, 14:32:09)
[GCC 3.3.5 20050117 (prerelease) (SUSE Linux)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> a_dictionary = {0: "zero", 1: "one"}
>>> for x in a:
...     print x
...
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
NameError: name 'a' is not defined
>>>

Ciao, Michael.