Tim Peters <t...@python.org> added the comment:
It's hard to be clearer without being annoyingly wordy. The truth is that sort does all comparisons by calling the CAPI: PyObject_RichCompareBool(v, w, Py_LT)` Sorting doesn't know (or care) how `PyObject_RichCompareBool()` is implemented. The closest Python equivalent is: bool(v < w) although then you also have to be clear that `bool` refers to the builtin function of that name. Regardless, the sorting docs certainly aren't the place to explain how `v < w` is implemented. For example, that it _may_ end up calling `w.__gt__(v)` has nothing to do with sorting - instead that's about the semantics of comparison operators, regardless of context. Since, best I can recall, nobody has asked about this before, perhaps the docs don't need "improvement" ;-) If they do, then I'm with Mark: the _intent_ was to say "if you want a class to implement its own sorting order, then it's sufficient to implement `__lt__` alone, and then sorting will use only that comparison operator if the list contains only instances of that class". ---------- _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue39210> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com