diff --git a/src/lib.rs b/src/lib.rs
index 0d43c51..760bda8 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -215,6 +215,7 @@ where
 mod tests {
     use super::*;
     use std::assert_matches::assert_matches;
+    use std::collections::HashMap;
 
     #[test]
     fn test_parsing() {
@@ -273,15 +274,24 @@ mod tests {
     <object>   ::= "{" [<property>] {"," <property>}* "}"
     <property> ::= <string> ":" <value>
     */
+    #[derive(Debug, Clone)]
+    enum JsonValue {
+        Null,
+        Bool(bool),
+        Str(String),
+        Num(f64),
+        Array(Vec<JsonValue>),
+        Object(HashMap<String, JsonValue>),
+    }
 
     #[test]
     fn parse_json() {
-        let json_null = literal("null");
-        let json_true = literal("true");
-        let json_false = literal("false");
+        let json_null = literal("null").to(JsonValue::Null);
+        let json_true = literal("true").to(JsonValue::Bool(true));
+        let json_false = literal("false").to(JsonValue::Bool(false));
 
         let json_value = choice(json_null, choice(json_true, json_false));
 
-        assert_matches!(json_value.parse("true"), Ok(("true", "")));
+        assert_matches!(json_value.parse("true"), Ok((JsonValue::Bool(true), "")));
     }
 }