Implement stronger mapped TypeScript type (#7)

sindresorhus · Feb 26, 2022 · 4b96de4 · 4b96de4
1 parent 9f03118
commit 4b96de4
Showing 1 changed file with 3 additions and 4 deletions.
diff --git a/index.d.ts b/index.d.ts
@@ -10,8 +10,7 @@ invertKeyValue({foo: 'bar', '🦄': '🌈'});
 ```
 */
 export default function invertKeyValue<
-	KeyType extends PropertyKey,
-	ValueType extends PropertyKey
+	T extends Record<PropertyKey, PropertyKey>
 >(
-	object: {[key in KeyType]: ValueType}
-): {[key in ValueType]: KeyType extends number ? Exclude<KeyType, number> | string : KeyType};
+	object: T
+): {[P in keyof T as T[P]]: keyof T extends number ? Exclude<keyof T, number> | string : P};