php vs python
Carl Banks
imbosol at vt.edu
Sun Jan 5 02:53:36 EST 2003
Afanasiy wrote:
> On Sat, 4 Jan 2003 21:21:05 -0500, pythonhda
> <pythonhda at yahoo.com.replacepythonwithlinux> wrote:
>
>>for key in d:
>> print key, '=', d[key]
>
> Someone please verify this example is incorrect.
No, it's correct. However, in versions of Python before 2.2, it won't
work because you cannot iterate over a dictionary. You would have to
do it this way:
for key in d.keys():
print key, '=', d[key]
> Putting the value in a variable named 'key' still
> makes it a value, not a key... Right?
>
> Wouldn't this code result in a no-index error on d[key] ?
No. In Python (starting with 2.2), iterating over a dictionary
iterates through the keys, not the values. Try this:
d = { 'a': 1, 'b': 2, 'c': 3 }
for x in d:
print x
It will print the keys a, b, and c (in no particular order), not the
values 1, 2, and 3. If you would like to iterate through the values
only, you could do this:
for value in d.values():
...
--
CARL BANKS
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