5 files changed, 20 insertions, 15 deletions
diff --git a/dhall/src/imports.rs b/dhall/src/imports.rs
index 8df4e97..96268ca 100644
--- a/dhall/src/imports.rs
+++ b/dhall/src/imports.rs
@@ -79,9 +79,9 @@ pub fn load_dhall_file(
         let resolve = |import: &Import| -> Expr<X, X> {
             resolve_import(import, &root).unwrap()
         };
-        expr.map_embed(&resolve).squash_embed()
+        expr.as_ref().map_embed(&resolve).squash_embed()
     } else {
-        panic_imports(&expr)
+        panic_imports(expr.as_ref())
     };
     Ok(expr)
 }
diff --git a/dhall/src/main.rs b/dhall/src/main.rs
index eb2206b..77f558c 100644
--- a/dhall/src/main.rs
+++ b/dhall/src/main.rs
@@ -65,7 +65,7 @@ fn main() {
         }
     };
 
-    let expr: SubExpr<_, _> = rc(imports::panic_imports(&expr));
+    let expr: SubExpr<_, _> = rc(imports::panic_imports(expr.as_ref()));
 
     let type_expr = match typecheck::type_of(expr.clone()) {
         Err(e) => {
diff --git a/dhall_core/src/core.rs b/dhall_core/src/core.rs
index 2d11068..3f01b55 100644
--- a/dhall_core/src/core.rs
+++ b/dhall_core/src/core.rs
@@ -305,30 +305,25 @@ impl<S: Clone, A: Clone> Expr<S, Expr<S, A>> {
 }
 
 impl<N, E> Clone for SubExpr<N, E> {
+    #[inline(always)]
     fn clone(&self) -> Self {
         SubExpr(Rc::clone(&self.0))
     }
 }
 
-impl<N, E> std::ops::Deref for SubExpr<N, E> {
-    type Target = Rc<Expr<N, E>>;
+impl<N, E> SubExpr<N, E> {
     #[inline(always)]
-    fn deref(&self) -> &Self::Target {
-        &self.0
+    pub fn as_ref(&self) -> &Expr<N, E> {
+        self.0.as_ref()
     }
 }
 
-// impl<N, E> SubExpr<N, E> {
-//     pub fn as_ref(&self) -> &Expr<N, E> {
-//         self.0.as_ref()
-//     }
-// }
-
 // Remains of a previous life, where everything was in Boxes
 pub fn bx<N, E>(x: Expr<N, E>) -> SubExpr<N, E> {
     SubExpr(Rc::new(x))
 }
 
+// Should probably rename this too
 pub fn rc<N, E>(x: Expr<N, E>) -> SubExpr<N, E> {
     SubExpr(Rc::new(x))
 }
@@ -414,7 +409,7 @@ where
         ExprF::Note(_, e) => {
             map_subexpr_rc_binder(e, map_expr, map_under_binder)
         }
-        _ => rc(map_subexpr(
+        e => rc(map_subexpr(
             e,
             map_expr,
             |_| unreachable!(),
diff --git a/dhall_core/src/printer.rs b/dhall_core/src/printer.rs
index b7d7506..fb3b8e8 100644
--- a/dhall_core/src/printer.rs
+++ b/dhall_core/src/printer.rs
@@ -217,6 +217,16 @@ impl<S, A: Display> Expr<S, A> {
     }
 }
 
+impl<S, A: Display> SubExpr<S, A> {
+    fn fmt_phase(
+        &self,
+        f: &mut fmt::Formatter,
+        phase: PrintPhase,
+    ) -> Result<(), fmt::Error> {
+        self.0.as_ref().fmt_phase(f, phase)
+    }
+}
+
 fn fmt_list<T, I, F>(
     open: &str,
     sep: &str,
diff --git a/dhall_generator/src/dhall_expr.rs b/dhall_generator/src/dhall_expr.rs
index c4b15e8..2e3adf7 100644
--- a/dhall_generator/src/dhall_expr.rs
+++ b/dhall_generator/src/dhall_expr.rs
@@ -10,7 +10,7 @@ pub fn dhall_expr(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
     let expr: SubExpr<X, Import> = parse_expr(&input_str).unwrap();
     let no_import =
         |_: &Import| -> X { panic!("Don't use import in dhall!()") };
-    let expr = rc(expr.map_embed(&no_import));
+    let expr = rc(expr.as_ref().map_embed(&no_import));
     let output = dhall_to_tokenstream_bx(&expr, &Context::new());
     output.into()
 }