最近看Node.js官方文档，格式化打印一个对象时，总能看到类似以下代码 ${data}：
console.log(stream instanceof EventEmitter); // true console.log(MyStream.super_ === EventEmitter); // true
stream.on('data', (data) => {
console.log(Received data: "${data}");
})
stream.write('It works!'); // Received data: "It works!"