delete dead code, fix typos in comments (#1923)

compiler/daml-lf-ast/src/DA/Daml/LF/Ast/Base.hs

@@ -393,7 +393,7 @@ data Expr
     , letBody    :: !Expr
       -- ^ Expression to bind variable in.
     }
-  -- | Concstruct empty list.
+  -- | Construct empty list.
   | ENil
     -- TODO(MH): When we move 'ECons' to 'BuiltinExpr' or remove it entirely,
     -- do the same to 'ENil'.

compiler/daml-lf-tools/src/DA/Daml/LF/TypeChecker/Env.hs

@@ -83,16 +83,6 @@ introTypeVar v k act = do
   whenM (views tvars (HMS.member v)) $ throwWithContext (EShadowingTypeVar v)
   local (tvars . at v ?~ k) act
 
--- -- | Introduce a fresh type variable to the environment. Uses the given name as
--- -- starting point for searching a fresh name. The fresh name finally found will
--- -- then be put in the enviroment and passed to the continuation.
--- introFreshTypeVar :: MonadGamma m => TypeVarName -> (TypeVarName -> m a) -> m a
--- introFreshTypeVar v act = do
---   let vs = v : map (\n -> fmap (<> T.pack (show n)) v) [1::Int ..]
---   -- NOTE(MH): This 'findM' cannot fail since @tvars@ is finite.
---   v' <- fromJust <$> findM (\v' -> not <$> view (tvars . contains v')) vs
---   introTypeVar v' (act v')
-
 -- | Run a computation in the current enviroment extended by a new term
 -- variable/type binding. Does not fail on shadowing.
 introExprVar :: MonadGamma m => ExprVarName -> Type -> m a -> m a

daml-foundations/daml-ghc/ghc-compiler/src/DA/Daml/GHC/Compiler/Convert.hs

@@ -25,7 +25,7 @@
 -- DICTIONARY SANITIZATION
 --
 -- GHC's desugaring for default methods relies on the the fact that Haskell is
--- lazy. In contract, DAML-LF is strict. This mismatch causes a few problems.
+-- lazy. In contrast, DAML-LF is strict. This mismatch causes a few problems.
 -- For instance, GHC desugars:
 --
 -- > class Foo a where
@@ -66,7 +66,7 @@
 --
 --
 --
--- GHC produces a @newtype@ rather than a @data@ type for dictionar types of
+-- GHC produces a @newtype@ rather than a @data@ type for dictionary types of
 -- type classes with a single method and no super classes. Since DAML-LF does
 -- not support @newtype@, we could either treat them as some sort of type
 -- synonym or translate them to a record type with a single field. We have