1 files changed, 6 insertions, 0 deletions
diff --git a/dhall/src/semantics/tck/env.rs b/dhall/src/semantics/tck/env.rs
index 3b02074..ba7fb73 100644
--- a/dhall/src/semantics/tck/env.rs
+++ b/dhall/src/semantics/tck/env.rs
@@ -120,3 +120,9 @@ impl TyEnv {
         self.items.lookup_ty(&var)
     }
 }
+
+impl<'a> From<&'a TyEnv> for &'a NzEnv {
+    fn from(x: &'a TyEnv) -> Self {
+        x.as_nzenv()
+    }
+}