声明一个扩展另一个多态类的多态类
问题描述：
我在React中编写了一个组件，它希望接收一个组件，该组件拥有一个通过ref访问的特定字段onPropChange作为道具。声明一个扩展另一个多态类的多态类
/* @flow */
import * as React from 'react';
type onPropChangeObject<Props> = {
[key: $Keys<Props>]: (newValue: any) => void
}
declare class PropWatchableComponent<DefaultProps, Props: Object, State>
extends React.Component<DefaultProps, Props, State>
{
onPropChange?: onPropChangeObject<Props>;
}
但类型检查失败，多个错误的流量（0.39.0）as seen here
8: declare class PropWatchableComponent<DefaultProps, Props: Object, State> extends React.Component<DefaultProps, Props, State> { ^undefined. Did you forget to declare some incompatible instantiation of `DefaultProps`?. This type is incompatible with
8: declare class PropWatchableComponent<DefaultProps, Props: Object, State> extends React.Component<DefaultProps, Props, State> { ^some incompatible instantiation of `DefaultProps`
8: declare class PropWatchableComponent<DefaultProps, Props: Object, State> extends React.Component<DefaultProps, Props, State> { ^undefined. Did you forget to declare some incompatible instantiation of `State`?. This type is incompatible with
8: declare class PropWatchableComponent<DefaultProps, Props: Object, State> extends React.Component<DefaultProps, Props, State> { ^some incompatible instantiation of `State`
8: declare class PropWatchableComponent<DefaultProps, Props: Object, State> extends React.Component<DefaultProps, Props, State> {
^DefaultProps. This type is incompatible with
8: declare class PropWatchableComponent<DefaultProps, Props: Object, State> extends React.Component<DefaultProps, Props, State> {
^undefined. Did you forget to declare DefaultProps?
8: declare class PropWatchableComponent<DefaultProps, Props: Object, State> extends React.Component<DefaultProps, Props, State> {
^State. This type is incompatible with
8: declare class PropWatchableComponent<DefaultProps, Props: Object, State> extends React.Component<DefaultProps, Props, State> {
^undefined. Did you forget to declare State?
的最新版本是什么这一切谈论不确定？我清楚地声明了DefaultProps和State作为类型参数。我忘了什么？