The Backpack patch.

Summary:
This patch implements Backpack for GHC.  It's a big patch but I've tried quite
hard to keep things, by-in-large, self-contained.

The user facing specification for Backpack can be found at:

    https://github.com/ezyang/ghc-proposals/blob/backpack/proposals/0000-backpack.rst

A guide to the implementation can be found at:

    https://github.com/ezyang/ghc-proposals/blob/backpack-impl/proposals/0000-backpack-impl.rst

Has a submodule update for Cabal, as well as a submodule update
for filepath to handle more strict checking of cabal-version.

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Test Plan: validate

Reviewers: simonpj, austin, simonmar, bgamari, goldfire

Subscribers: thomie, mpickering

Differential Revision: https://phabricator.haskell.org/D1482

1 files changed, 8 insertions, 8 deletions

diff --git a/testsuite/tests/haddock/haddock_examples/haddock.Test.stderr b/testsuite/tests/haddock/haddock_examples/haddock.Test.stderr
index 77286daf62..c2994dc1a5 100644
--- a/testsuite/tests/haddock/haddock_examples/haddock.Test.stderr
+++ b/testsuite/tests/haddock/haddock_examples/haddock.Test.stderr
@@ -1,17 +1,17 @@
-[1 of 3] Compiling Visible          ( Visible.hs, Visible.o )
+[1 of 3] Compiling Hidden           ( Hidden.hs, Hidden.o )
 
 ==================== Parser ====================
-module Visible where
-visible :: Int -> Int
-visible a = a
+module Hidden where
+hidden :: Int -> Int
+hidden a = a
 
 
-[2 of 3] Compiling Hidden           ( Hidden.hs, Hidden.o )
+[2 of 3] Compiling Visible          ( Visible.hs, Visible.o )
 
 ==================== Parser ====================
-module Hidden where
-hidden :: Int -> Int
-hidden a = a
+module Visible where
+visible :: Int -> Int
+visible a = a
 
 
 [3 of 3] Compiling Test             ( Test.hs, Test.o )