//将js对象转化为JSON字符
var obj2 = JSON.parse(str1);

var jsonstr = JSON.stringify(jsonObject);

interface Foo {
  a: string;
}
type Bar = Foo & {
  b: number;
};

Omit去掉
Partial可选
keyof
Pick选取
extends 继承
Dictionary&Many

let node = {
  type: 'Identifier',
  name: 'foo',
};
let { type: localType, name: localName } = node;
console.log(localType); // "Identifier"
console.log(localName); // "foo"

let node = {
  type: 'Identifier',
  name: 'foo',
};
let { type, name, value = true } = node;
console.log(type); // "Identifier"
console.log(name); // "foo"
console.log(value); // true

let node = {
  type: 'Identifier',
  name: 'foo',
  loc: {
    start: {
      line: 1,
      column: 1,
    },
    end: {
      line: 1,
      column: 4,
    },
  },
};
let {
  loc: { start },
} = node;
console.log(start.line); // 1
console.log(start.column); // 1

const groupId = Number(id);
const groupId = id as number;

//下面的在tsx中不能使用
const groupId = <number>id;