On Tue, 06 Oct 2009 23:20:13 -0700, Paul Rubin wrote: > Bearophile <bearophileh...@lycos.com> writes: >> sorting, and something that's surely not bug-prone. In such situation >> having a 'key' argument is *better*. Such sort can be stable. > > Nothing stops comparison sorting from being stable. Since the rest of > your post seems premised on the opposite, I hope that clears things up > for you.
I'm sure Paul already knows this, but key-based sorts are comparison sorts. There are two basic types of sorts: comparison based, where the routine has to compare items (usually with the < operator), and non-comparison sorts, like bucket sort, pigeon-hole sort and radix sort. These sorts require special knowledge of the items being sorted, and don't need to compare two items. General purpose sorts like Python's sort() do, regardless of whether you pass a key function, a three-way comparison function, or something else. -- Steven -- http://mail.python.org/mailman/listinfo/python-list
