On Dec 19, 2010, at 10:41 AM, Guido van Rossum wrote: > On Sun, Dec 19, 2010 at 5:13 AM, Antoine Pitrou <solip...@pitrou.net> wrote: >> On Sat, 18 Dec 2010 20:23:49 -0800 >> Guido van Rossum <gu...@python.org> wrote: >>> I may be unique, but I fear there is no great answer. On the one hand >>> I almost always code it as e.g. assertEqual(actual, expected), which >>> matches my preference for e.g. "if x == 5:" rather than "if 5 == x:". >>> On the other hand in those assert* functions that show a nice diff of >>> two lists, when reading such a diff my expectation is that "old, new" >>> corresponds to "expected, actual". Which then freaks me out until I >>> realize that I coded it as "actual, expected"... And yet "expected, >>> actual" still looks weird to me. :-( >> >> This could be nicely resolved by renaming the arguments "a" and "b", >> and having the diff display "a, b". It's quite natural (both the diff >> ordering and the arguments ordering), and they are consistent with each >> other. > > So 'a' stands for 'after' and 'b' for 'before', right? :-)
If you go down the a / b path instead of actual/expected, the diffs are straight-forward but some of the other output styles needed to be changed also (replace the messages for "unexpected" and "missing" elements to "things in a but not in b" and "things in b but not in a". Raymond _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com