[project @ 2001-05-09 13:28:11 by simonpj]

[project @ 2001-05-09 13:28:11 by simonpj]
****	MERGE WITH 5.00 BRANCH     ********

	-------------------------------
	Fix a rather obscure rule bogon
	-------------------------------

The problem was that there was

	class Foo a where
	  op :: a -> a

	{-# RULES "op" op x = x #-}

or something like that.  We attach locally defined rules, like this one,
to the local binding, in SimplCore.prepareRules.  Alas op doesn't reply
"True" to isLocalId, because it's a class selector (so it's a GlobalId
throughout).   Result: we treated the rule as an imported rule, and
therefore gave 'op' a fresh unique (becuase it looked as if it was
already in scope).  This only blew up in ghc --make or --interactive.

The handling of local vs global rules is rather unsatisfactory.
Something to muse on.