strings and sort()

[Paul Rubin]

caljason76 at yahoo.com (Jason) writes:
> How do I sort the characters in a string, so far I use this:
>         a="qwerasdfzxcv"
>         b=[x for x in a]
>         b.sort()

You could also say 

  a = "qwerasdfzxcv"
  b = list(a)
  b.sort()

That might run a little faster than the list comprehension version,
plus it's more portable to older Python versions.

> Why doesn't sort() return the sorted list.  I would like to chain it
> to other operations:
>         b=[x for x in a].sort()

In Python, that's considered immoral--it puts you in danger of
forgetting that the sort operation modifies the list that you use it
on.  For example, if you say

   a = b.sort()

expecting to get a sorted copy of b without clobbering b, you'd get
a rude surprise.