Another dict method...

[Alex Martelli]

"Stephen Hansen" <news at myNOSPAM.org> wrote in message
news:imnN6.41384$154.11548822 at typhoon.we.rr.com...
> ... Dictionaries aren't sorted, and I can't imagine an iterator is going
to
> go through the trouble of sorting them. Even with iterators, if you wish
to
> iterate over a dictionary in sorted order, you'll have to do what you do
> now, I believe... that is, extract the .keys() and sort them, then iterate
> over them.
>
>     for key in dict.keys().sort()

No -- the .sort() method sorts a list in-place and returns None.  You
need a little auxiliary function:

    def sorted_inplace(alist):
        alist.sort()
        return alist

    for key in sorted_inplace(dict.keys()):


No need to make a copy of the list before sorting it, in this case, as it's
a temporary list.  To avoid altering other lists, in other cases you might
prefer the following auxiliary function:

    def sorted_copy(alist):
        return sorted_inplace(alist[:])

where the whole-list-slice [:] is the normal idiom to copy a list.


Alex