Remove one more instance of duplicate typechecking

2 files changed, 16 insertions, 1 deletions

diff --git a/dhall/src/expr.rs b/dhall/src/expr.rs
index 9e89e3a..7c62a33 100644
--- a/dhall/src/expr.rs
+++ b/dhall/src/expr.rs
@@ -120,6 +120,9 @@ impl<'a> Normalized<'a> {
     pub(crate) fn into_expr(self) -> SubExpr<X, X> {
         self.0
     }
+    pub(crate) fn unnote<'b>(self) -> Normalized<'b> {
+        Normalized(self.0, self.1, PhantomData)
+    }
     pub(crate) fn into_type(self) -> Type<'a> {
         Type(match self.0.as_ref() {
             ExprF::Const(c) => TypeInternal::Const(*c),
@@ -128,6 +131,18 @@ impl<'a> Normalized<'a> {
     }
 }
 
+#[doc(hidden)]
+impl<'a> Type<'a> {
+    pub(crate) fn unnote<'b>(self) -> Type<'b> {
+        use TypeInternal::*;
+        Type(match self.0 {
+            Expr(e) => Expr(Box::new(e.unnote())),
+            Const(c) => Const(c),
+            SuperType => SuperType,
+        })
+    }
+}
+
 impl<'a> SimpleType<'a> {
     pub(crate) fn into_type(self) -> Type<'a> {
         Normalized(self.0, Some(Type::const_type()), PhantomData).into_type()
diff --git a/dhall/src/typecheck.rs b/dhall/src/typecheck.rs
index 195628b..c8929fe 100644
--- a/dhall/src/typecheck.rs
+++ b/dhall/src/typecheck.rs
@@ -22,7 +22,7 @@ impl<'a> Resolved<'a> {
         ty: &Type,
     ) -> Result<Typed<'static>, TypeError> {
         let expr: SubExpr<_, _> = self.0.unnote();
-        let ty: SubExpr<_, _> = ty.as_normalized()?.as_expr().absurd();
+        let ty: SubExpr<_, _> = ty.clone().unnote().embed()?;
         type_of(dhall::subexpr!(expr: ty))
     }
     /// Pretends this expression has been typechecked. Use with care.