TcSimplify.reduceImplication: clean up
authorManuel M T Chakravarty <chak@cse.unsw.edu.au>
Wed, 1 Oct 2008 09:13:15 +0000 (09:13 +0000)
committerManuel M T Chakravarty <chak@cse.unsw.edu.au>
Wed, 1 Oct 2008 09:13:15 +0000 (09:13 +0000)
commitcfda0421ca2c7c5f762814fd25988cf89871f1d8
tree43367f50d2f53009325d4370153d4aece4722054
parent1add6282808b5ae98e72ef7034634036c9b91b04
TcSimplify.reduceImplication: clean up
- This cleans up some of the mess in reduceImplication and documents the
  precondition on the form of wanted equalities properly.
- I also made the back off test a bit smarter by allowing to back off in the
  presence of wanted equalities as long as none of them got solved in the
  attempt.  (That should save generating some superfluous bindings.)

  MERGE TO 6.10
compiler/typecheck/Inst.lhs
compiler/typecheck/TcSimplify.lhs
compiler/typecheck/TcTyFuns.lhs