add invalidate() method

src/async.ts

@@ -75,6 +75,10 @@ export interface MemoAsyncStoredResult<T extends AsyncFunc> {
 	timer: ReturnType<typeof setTimeout>;
 }
 
+export type MemoizedAsyncFunc<T extends AsyncFunc> = T & {
+	invalidate(...params: Params<T>) : void;
+};
+
 export function memo_async<T extends AsyncFunc>(opts: MemoAsyncOptions<T>) : T {
 	const get_key = opts.key ?? default_key;
 	const storage: Record<string, MemoAsyncStoredResult<T>> = Object.create(null);
@@ -230,7 +234,15 @@ export function memo_async<T extends AsyncFunc>(opts: MemoAsyncOptions<T>) : T {
 		}
 	}
 	
-	return memoized as unknown as T;
+	memoized.invalidate = function invalidate(...params: Params<T>) {
+		const key = get_key(params);
+
+		if (storage[key]) {
+			evict(storage[key]);
+		}
+	};
+	
+	return memoized as unknown as MemoizedAsyncFunc<T>;
 }
 
 function default_key(...params: any[]) : string {

src/full.ts

@@ -54,7 +54,11 @@ export interface MemoStoredResult<T extends Func> {
 	timer: ReturnType<typeof setTimeout>;
 }
 
-export function memo<T extends Func>(opts: MemoOptions<T>) : T {
+export type MemoizedFunc<T extends Func> = T & {
+	invalidate(...params: Params<T>) : void;
+};
+
+export function memo<T extends Func>(opts: MemoOptions<T>) : MemoizedFunc<T> {
 	const get_key = opts.key ?? default_key;
 	const storage: Record<string, MemoStoredResult<T>> = Object.create(null);
 
@@ -76,6 +80,11 @@ export function memo<T extends Func>(opts: MemoOptions<T>) : T {
 			const evicted = storage[key];
 			delete storage[key];
 
+			if (evicted.timer) {
+				clearTimeout(evicted.timer);
+				evicted.timer = null;
+			}
+
 			if (opts.on_evict) {
 				opts.on_evict(evicted);
 			}
@@ -99,8 +108,13 @@ export function memo<T extends Func>(opts: MemoOptions<T>) : T {
 		record.expires = record.created + ttl;
 		record.timer = setTimeout(() => evict(record.key), ttl);
 	}
+
+	memoized.invalidate = function invalidate(...params: Params<T>) {
+		const key = get_key(params);
+		evict(key);
+	};
 	
-	return memoized as unknown as T;
+	return memoized as unknown as MemoizedFunc<T>;
 }
 
 function default_key(...params: any[]) : string {