#16536: Python 3 preparation: cmp parameter of sorted() function and L.sort()
method are gone
-----------------------------+----------------------------
Reporter: wluebbe | Owner:
Type: PLEASE CHANGE | Status: new
Priority: major | Milestone: sage-6.3
Component: distribution | Keywords: python3
Merged in: | Authors:
Reviewers: | Report Upstream: N/A
Work issues: | Branch:
Commit: | Dependencies:
Stopgaps: |
-----------------------------+----------------------------
In Py2 the standard function
[[https://docs.python.org/2/library/functions.html#sorted|sorted()]] and
the mutable list method [[https://docs.python.org/2/library/stdtypes.html
#mutable-sequence-types|sort()]] both have an optional parameter
{{{cmp=}}} that takes a custom comparison function of two arguments.
The parameter is no more available in Py3.
The recommended way is to use the {{{key=}}} which specifies a function of
one argument that is used to extract a comparison key from each list
element. This has also better performance.
While there is a function
[[https://docs.python.org/2/library/functools.html#functools.cmp_to_key|functools.cmp_to_key()]]
to convert an old-style cmp function to a key function, it is preferable
to directly use an appropriate key function.
This ticket is tracked as a dependency of meta-ticket ticket:15980.
--
Ticket URL: <http://trac.sagemath.org/ticket/16536>
Sage <http://www.sagemath.org>
Sage: Creating a Viable Open Source Alternative to Magma, Maple, Mathematica,
and MATLAB
--
You received this message because you are subscribed to the Google Groups
"sage-trac" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
To post to this group, send email to [email protected].
Visit this group at http://groups.google.com/group/sage-trac.
For more options, visit https://groups.google.com/d/optout.
