a question regarding conciseness

[Christophe Delord]

Python help says :
---
Help on built-in function sort:

sort(...)
     L.sort([cmpfunc]) -- sort *IN PLACE*; if given, cmpfunc(x, y) -> 
-1, 0, 1
---

sort returns nothing, it just sorts the list :

 >>> print [].sort()
None

Writting a function to sort lists may not be efficient :

def my_sort(L):
     L2 = L[:]
     L2.sort()
     return L2

X = [...]
for x in my_sort(X):
     ....


Christophe.

Rajarshi Guha wrote:

> Hi,
>   I have a dictionary and would like to loop over the elements in sorted 
> order.
> The dictionary is of the form:
> 
> {'1':'option1', '2':'option2', '3':'option3'}
> 
> However when I use:
> 
> for i in d.keys().sort():
>   do something
> 
> I get:
> 
> Traceback (innermost last):
>   File "<stdin>", line 1, in ?
> TypeError: loop over non-sequence
> 
> But I know that d.keys() returns a list to which the sort() function should 
> be applicable.
> 
> When I do:
> 
> k = d.keys()
> k.sort()
> for i in k:
>   do something
> 
> it works fine.
> Why can't I use d.keys().sort() directly? And is there any other more 
> concise (elegent?) way to loop over sorted dictionary keys?
> 
> TIA,
> 
>