[m-rev.] for review: better diagnostics for currying multimode predicates

[Peter Wang]

On Wed, 07 Jun 2017 10:48:21 +1000 (AEST), "Zoltan Somogyi" <zoltan.somogyi at runbox.com> wrote:
> The motivation for this diff is the not-at-all-useful error message
> we used to get for currying uint.xor after Julien uncommented
> its new modes.
> 
> For review by anyone.
> 

> tests/invalid/uint_bitwise_xor_mode.{m,err_exp}:
>     A new test case for both improvements. It is a version of
>     tests/hard_coded/uint_bitwise.m cut down to contain just the bug
>     that previously we generate only a misleading error message for.

That looks fine to me. I suggest naming the new test case
to reflect what it tests.

Peter