General FAQ: list.sort() out of date

[tcdelaney]

BPO	1095342

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assignee = None
closed_at = <Date 2005-01-08.12:41:15.000>
created_at = <Date 2005-01-03.23:16:48.000>
labels = []
title = 'General FAQ: list.sort() out of date'
updated_at = <Date 2005-01-08.12:41:15.000>
user = 'https://bugs.python.org/tcdelaney'

bugs.python.org fields:

activity = <Date 2005-01-08.12:41:15.000>
actor = 'jlgijsbers'
assignee = 'jlgijsbers'
closed = True
closed_date = None
closer = None
components = ['None']
creation = <Date 2005-01-03.23:16:48.000>
creator = 'tcdelaney'
dependencies = []
files = []
hgrepos = []
issue_num = 1095342
keywords = []
message_count = 4.0
messages = ['23861', '23862', '23863', '23864']
nosy_count = 2.0
nosy_names = ['jlgijsbers', 'tcdelaney']
pr_nums = []
priority = 'normal'
resolution = 'accepted'
stage = None
status = 'closed'
superseder = None
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url = 'https://bugs.python.org/issue1095342'
versions = []

[tcdelaney]

http://www.python.org/doc/faq/general.html#why-
doesn-t-list-sort-return-the-sorted-list

specifies the idiom:

keys = dict.keys()
keys.sort()
for key in keys:
        ...do whatever with dict[key]...

and doesn't mention sorted().

I would suggest the following wording be used:

In situations where performance matters, making a copy
of the list just to sort it would be wasteful. Therefore,
list.sort() sorts the list in place. In order to remind you
of that fact, it does not return the sorted list. This way,
you won't be fooled into accidentally overwriting a list
when you need a sorted copy but also need to keep the
unsorted version around.

In Python 2.4 a new builtin - sorted() - has been added.
This function creates a new list from the passed
iterable, sorts it and returns it.

As a result, here's the idiom to iterate over the keys of a
dictionary in sorted order:

for key in sorted(dict.iterkeys()):
        ...do whatever with dict[key]...

[tcdelaney]

Logged In: YES
user_id=603121

Do we want to also reference the 2.3 and earlier idiom?

[tcdelaney]

Logged In: YES
user_id=603121

Updated text:

In situations where performance matters, making a copy
of the list just to sort it would be wasteful. Therefore,
list.sort() sorts the list in place. In order to remind you
of that fact, it does not return the sorted list. This way,
you won't be fooled into accidentally overwriting a list
when you need a sorted copy but also need to keep the
unsorted version around.

In Python 2.4 a new builtin - sorted() - has been added.
This function creates a new list from a passed
iterable, sorts it and returns it.

As a result, here's the idiom to iterate over the keys of a
dictionary in sorted order:

for key in sorted(dict.iterkeys()):
    ...do whatever with dict[key]...

Versions of Python prior to 2.4 need to use the following idiom:

keys = dict.keys()
keys.sort()
for key in keys:
    ...do whatever with dict[key]...

[jlgijsbers]

Logged In: YES
user_id=469548

Fixed in rev 1.22 of general.ht. Thanks for the new text!