add typings for createEventDispatcher (sveltejs#5260)

taylorzane · Dec 17, 2020 · 4dcd950 · 4dcd950
1 parent e030c11
commit 4dcd950
Showing 1 changed file with 4 additions and 2 deletions.
diff --git a/src/runtime/internal/lifecycle.ts b/src/runtime/internal/lifecycle.ts
@@ -27,7 +27,9 @@ export function onDestroy(fn) {
 	get_current_component().$$.on_destroy.push(fn);
 }
 
-export function createEventDispatcher() {
+export function createEventDispatcher<
+	EventMap extends {} = any
+>(): <EventKey extends Extract<keyof EventMap, string>>(type: EventKey, detail?: EventMap[EventKey]) => void {
 	const component = get_current_component();
 
 	return (type: string, detail?: any) => {
@@ -61,4 +63,4 @@ export function bubble(component, event) {
 	if (callbacks) {
 		callbacks.slice().forEach(fn => fn(event));
 	}
-}
+}