Make benign non-determinism in pretty-printing more obvious
authorBartosz Nitka <niteria@gmail.com>
Mon, 18 Apr 2016 14:32:03 +0000 (07:32 -0700)
committerBartosz Nitka <niteria@gmail.com>
Fri, 22 Apr 2016 16:09:24 +0000 (09:09 -0700)
commit0f96686b10fd36d479a54c71a6e1753193e85347
tree58a9d65664645e9ae99fa3385d66919acb8fb97a
parenta9076fc2685b296bf5a32ff978c5eec91f67fd6a
Make benign non-determinism in pretty-printing more obvious

This change takes us one step closer to being able to remove
`varSetElemsWellScoped`. The end goal is to make every source
of non-determinism obvious at the source level, so that when
we achieve determinism it doesn't get broken accidentally.

Test Plan: compile GHC

Reviewers: simonmar, goldfire, simonpj, austin, bgamari

Reviewed By: simonpj

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D2123

GHC Trac Issues: #4012
compiler/basicTypes/VarSet.hs
compiler/typecheck/FamInst.hs
compiler/typecheck/FunDeps.hs
compiler/utils/UniqFM.hs