How to use "??=" syntax in Typescript

Question

let a;
a ??= 'asd'
console.log(a); // asd

When I run the above js in the browser console without any problems

However, when I run in typescript, an error occurs

SyntaxError: Unexpected token '??='

This is my configuration:

    "typescript": "^4.1.3",
    "webpack": "^5.11.0",
    "webpack-cli": "^4.2.0"

    "target": "ESNext",
    "module": "ESNext",

I want to use "??=", need to configure webpack or tsconfig, thanks

Answer 1

After using both "babel-loader" and "ts-loader", the "??=" syntax can be used normally

  rules: [
    {
      test: /.tsx?$/,
      exclude: /(node_modules|bower_components)/,
      use: [
        {
          loader: "babel-loader",
          options: {
            presets: ["@babel/env"],
          },
        },
        {
          loader: "ts-loader",
        },
      ],
    },
  ],