Remove unused things from utils/Digraph
authorDavid Feuer <david.feuer@gmail.com>
Sun, 13 May 2018 22:34:38 +0000 (18:34 -0400)
committerBen Gamari <ben@smart-cactus.org>
Sun, 13 May 2018 22:34:43 +0000 (18:34 -0400)
commitcdbe00fe24e25f7ba06d15990a37ba4f3f6098ab
treeac74d149ad80a1f22614cf8a7c7b0e3d9298aa39
parent2828dbf487c54d57b82578cc0872a348cfb173f3
Remove unused things from utils/Digraph

`utils/Digraph` had a bunch of code that wasn't actually being used,
much of which wasn't documented at all, some of which was clearly
ill-considered, and some of which was documented as being inefficient.

Remove all unused code from that module except for the obvious and
innocuous `emptyG`.

Reviewers: bgamari

Reviewed By: bgamari

Subscribers: rwbarton, thomie, carter

Differential Revision: https://phabricator.haskell.org/D4676
compiler/utils/Digraph.hs