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Tue Oct 21 07:00:42 EDT 2003 · https://mail.python.org/pipermail/python-dev/2003-October/039131.html

On Tuesday 21 October 2003 12:31 pm, Mark Russell wrote:
> On Mon, 2003-10-20 at 23:49, Guido van Rossum wrote:
> > Really?  That would seem to just obfuscate things for the reader (who
> > would have to scroll back potentially many pages to find the one-line
> > definition of sort).
>
> I think most readers would probably be able to guess what
>
> 	for key in sort(d.keys()):
>
> would do.  If not then it's no worse than a user-defined function.

Incidentally,
    for k in list.sorted(d):
will be marginally faster, e.g. (using the copysort I posted here, without The 
Trick -- it should be just about identical to the list.sorted classmethod):

import copysort

x = dict.fromkeys(map(str,range(99999)))

def looponkeys(x, c=copysort.copysort):
    for k in c(x.keys()): pass

def loopondict(x, c=copysort.copysort):
    for k in c(x): pass

[alex at lancelot ext]$ timeit.py -c -s'import t' 't.loopondict(t.x)'
10 loops, best of 3: 2.84e+05 usec per loop
[alex at lancelot ext]$ timeit.py -c -s'import t' 't.looponkeys(t.x)'
10 loops, best of 3: 2.67e+05 usec per loop

i.e., about 10% better for this size of list and number of runs (quite a few,
eyeball x.keys()...:-).  Nothing crucial, of course, but still.

Moreover, "list.sorted(d)" and "sort(d.keys())" are the same length, and
the former is conceptually simpler (one [explicit] method call, vs one method
call and one function call).  Of course, if each keystroke count, you may
combine both "abbreviations" and just use "sort(d)".

>        for key, value in d.sort():
>
> (i.e. adding a sort() instance method to dict equivalent to:

Why should multiple data types acquire separate .sort methods with
subtly different semantics (one works in-place and returns None, one
doesn't mutate the object and returns a list, ...) when there's no real
added value wrt ONE classmethod of list...?  Particularly with cmp,
key, and reverse on each, seems cumbersome to me.  Truly, is
list.sorted(d.iteritems())  [or d.items() if you'd rather save 4 chars
than a small slice of time:-)] SO "unobvious"?  I just don't get it.

Alex

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Showing content from https://mail.python.org/pipermail/python-dev/2003-October/039131.html below:

copysort patch, was RE: [Python-Dev] inline sort option