add typings for createEventDispatcher (#5260)

dummdidumm · web-flow · commit aa7e5e32b156 · 2020-08-12T17:05:49.000-04:00
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));
 	}
-}
+}

Original file line number	Diff line number	Diff line change
`@@ -27,7 +27,9 @@ export function onDestroy(fn) {`
`27`	`27`	`get_current_component().$$.on_destroy.push(fn);`
`28`	`28`	`}`
`29`	`29`
`30`		`-export function createEventDispatcher() {`
	`30`	`+export function createEventDispatcher<`
	`31`	`+ EventMap extends {} = any`
	`32`	`+>(): <EventKey extends Extract<keyof EventMap, string>>(type: EventKey, detail?: EventMap[EventKey]) => void {`
`31`	`33`	`const component = get_current_component();`
`32`	`34`
`33`	`35`	`return (type: string, detail?: any) => {`
`@@ -61,4 +63,4 @@ export function bubble(component, event) {`
`61`	`63`	`if (callbacks) {`
`62`	`64`	`callbacks.slice().forEach(fn => fn(event));`
`63`	`65`	`}`
`64`		`-}`
	`66`	`+}`