diff options
| author | Ryan Scott <ryan.gl.scott@gmail.com> | 2017-02-21 09:43:43 -0500 |
|---|---|---|
| committer | Ryan Scott <ryan.gl.scott@gmail.com> | 2017-02-21 09:43:43 -0500 |
| commit | 4080a63c510f13be22953383a07ce0cf2d29e17b (patch) | |
| tree | fa6a3c028842815a311c761f128ec835d5d434b5 /compiler | |
| parent | 6e3288473718fcd8e6ad15a5e7db5b7ab43e9cbb (diff) | |
| download | haskell-4080a63c510f13be22953383a07ce0cf2d29e17b.tar.gz | |
Minor spelling, grammar, and formatting fixes
[ci skip]
Diffstat (limited to 'compiler')
| -rw-r--r-- | compiler/typecheck/TcDerivInfer.hs | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/compiler/typecheck/TcDerivInfer.hs b/compiler/typecheck/TcDerivInfer.hs index 22c05033bf..a28b0bcf65 100644 --- a/compiler/typecheck/TcDerivInfer.hs +++ b/compiler/typecheck/TcDerivInfer.hs @@ -34,7 +34,7 @@ import Type import TcSimplify import TcValidity (validDerivPred) import TcUnify (buildImplicationFor) -import Unify ( {- tcMatchTy, -} tcUnifyTy) +import Unify (tcUnifyTy) import Util import Var import VarEnv @@ -592,7 +592,7 @@ simplifyDeriv pred tvs thetas -- Create the implications we need to solve. For stock and newtype -- deriving, these implication constraints will be simple class - -- constriants like (C a, Ord b). + -- constraints like (C a, Ord b). -- But with DeriveAnyClass, we make an implication constraint. -- See Note [Gathering and simplifying constraints for DeriveAnyClass] mk_wanteds :: ThetaOrigin -> TcM WantedConstraints @@ -716,8 +716,8 @@ To see why, consider this example of DeriveAnyClass: default baz :: (Ord a, Show a) => a -> a -> Bool baz x y = compare x y == EQ -Because 'bar' and 'baz' have default signatures, generates a top-level -definition for thse generic default methods +Because 'bar' and 'baz' have default signatures, this generates a top-level +definition for these generic default methods $gdm_bar :: forall a. Foo a => forall c. (Show a, Ix c) @@ -737,14 +737,15 @@ GHC were typechecking the binding bar = $gdm bar it would * skolemise the expected type of bar - * instaniate the type of $dm_bar with meta-type varibles + * instantiate the type of $dm_bar with meta-type varibles * build an implication constraint [STEP DAC BUILD] So that's what we do. We build the constraint (call it C1) forall b. Ix b => (Show (Maybe s), Ix cc, - Maybe s -> b -> String ~ Maybe s -> cc -> String) + Maybe s -> b -> String + ~ Maybe s -> cc -> String) The 'cc' is a unification variable that comes from instantiating $dm_bar's type. The equality constraint comes from marrying up |