Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
3.4k views
in Technique[技术] by (71.8m points)

typescript 函数声明使用: 和=> 有什么不同?

interface Animal { Eat(): void }

interface Dog extends Animal{ Bark():void }

interface Cat extends Animal{ Meow():void }

interface ComparerA<T> {
    compareA: (a: T, b: T) => number;
}
interface ComparerB<T> {
    compareA(a: T, b: T): number;
}
declare let animalA: ComparerA<Animal>;
declare let dogA: ComparerA<Dog>;

declare let animalB: ComparerB<Animal>;
declare let dogB: ComparerB<Dog>;

animalA = dogA; // 错误
dogA = animalA;  // 正确

animalB = dogB; // 正确
dogB = animalB;  // 正确

为什么: 和=> 声明出来的函数会有区别 一个是逆变 一个是双向协变呢?


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Answer

0 votes
by (71.8m points)

没有差别的。如果报错检查下typescript的版本。


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...