diff --git a/implementations/rust/preserves-schema/src/support/mod.rs b/implementations/rust/preserves-schema/src/support/mod.rs
index 8e40a84..8337ad4 100644
--- a/implementations/rust/preserves-schema/src/support/mod.rs
+++ b/implementations/rust/preserves-schema/src/support/mod.rs
@@ -23,8 +23,8 @@ pub trait Parse<L, Value: NestedValue>: Sized {
     fn parse<'a, LL: Into<&'a L>>(language: LL, value: &Value) -> Result<Self, ParseError> where L: 'a;
 }
 
-impl<L, Value: NestedValue> Parse<L, Value> for Value {
-    fn parse<'a, LL: Into<&'a L>>(_language: LL, value: &Value) -> Result<Self, ParseError> where L: 'a {
+impl<Value: NestedValue> Parse<(), Value> for Value {
+    fn parse<'a, LL: Into<&'a ()>>(_language: LL, value: &Value) -> Result<Self, ParseError> {
         Ok(value.clone())
     }
 }
@@ -33,8 +33,8 @@ pub trait Unparse<L, Value: NestedValue> {
     fn unparse<'a, LL: Into<&'a L>>(&self, language: LL) -> Value where L: 'a;
 }
 
-impl<L, Value: NestedValue> Unparse<L, Value> for Value {
-    fn unparse<'a, LL: Into<&'a L>>(&self, _language: LL) -> Value where L: 'a {
+impl<Value: NestedValue> Unparse<(), Value> for Value {
+    fn unparse<'a, LL: Into<&'a ()>>(&self, _language: LL) -> Value {
         self.clone()
     }
 }