On Sat, Jul 24, 2010 at 11:54 AM, Rob Beezer <goo...@beezer.cotse.net> wrote: > So it is a verb. ;-) > > Looks like similar comments apply to edges(). > > I'm thinking that optionally passing in a comparison function would be > a nice thing to add - a minor convenience, but also it would drive > home the point that the sorting is somewhat the caller's > responsibility in non-trivial situations (ie for not most users). > > I'll get a ticket started soon.
Note that Python 3 has removed the comparison function argument for List.sort() and similar functions, in favor of a "key" argument giving a function that transforms a list element into a sortable element. For example, if you want to sort by string representations, currently you could do: verts.sort(cmp=lambda a, b: cmp(str(a), str(b))) but in Python 3 you would have to do: verts.sort(key=str) The idea is to discourage inefficient programming; the Python 3 version is better, because it calls str() on each element only once, whereas the old version calls str() on each element O(log(N)) times. Our current Python also has a key= argument for sort(). I suggest that we should follow Python 3 here for such APIs, and optionally pass in a key= function rather than a cmp= comparison function. Carl -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
