How can you be sure that you get a certain error? Depending on the order of evaluation you might get different error messages if there are multiple possible ways to fail. I think automated testing against specific error messages will not work reliably.
On Tue, 27 Nov 2012, Michael Snoyman wrote:
+1 on the proposal. Even if I'm opposed to partial functions, I'm in favor of making it easier to test them reliably.