element-plus/packages/utils/types.ts
2020-09-04 14:59:29 +08:00

19 lines
692 B
TypeScript

type OptionalKeys<T extends Record<string, unknown>> = {
[K in keyof T]: T extends Record<K, T[K]>
? never
: K
}[keyof T]
type RequiredKeys<T extends Record<string, unknown>> = Exclude<keyof T, OptionalKeys<T>>
type MonoArgEmitter<T, Keys extends keyof T> = <K extends Keys>(evt: K, arg?: T[K]) => void
type BiArgEmitter<T, Keys extends keyof T> = <K extends Keys>(evt: K, arg: T[K]) => void
export type EventEmitter<T extends Record<string, unknown>> =
MonoArgEmitter<T, OptionalKeys<T>> & BiArgEmitter<T, RequiredKeys<T>>
export type AnyFunction<T> = (...args: any[]) => T
export type PartialReturnType<T extends (...args: unknown[]) => unknown> = Partial<ReturnType<T>>