基础

泛型工具

Required

将类型的属性变成必选

interface Person {
  name?: string;
  age?: number;
  hobby?: string[];
}

type Required<T> = {
  [Key in keyof T]-?: T[Key];
};

const user: Required<Person> = {
  name: "树哥",
  age: 18,
  hobby: ["code"],
};

在这里 -? 是一个非常有意思的写法，相当于把可选去掉

Partial

Exclude

Extract

Readonly

Record

Pick

Omit

NonNullable

ReturnType

Parameters