(_a = [""], _a.raw = [""],....); js一个小括号的是什么意思？

Question

用typescript编译出来的代码，如下：

typescript:

function test(template, name, age) {
    console.log(template);
    console.log(name);
    console.log(age);
}
let myname: string = "Keyon";
let myage: number = 18;
test`Hello, my name is ${myname}, I'm ${myage}.`;

编译后的javascript:

function test(template, name, age) {
    console.log(template);
    console.log(name);
    console.log(age);
}
var myname = "Keyon";
var myage = 18;
(_a = ["Hello, my name is ", ", I'm ", "."], _a.raw = ["Hello, my name is ", ", I'm ", "."], test(_a, myname, myage));
var _a;

(_a = ["Hello, my name is ", ", I'm ", "."], _a.raw = ["Hello, my name is ", ", I'm ", "."], test(_a, myname, myage));这里直接一个小括号，里边的像参数一样的，是什么意思？还有那个 _a.raw 是什么？

Answer 1

括起来执行多个表达式

Answer 2

你可以在第一段代码的test函数内打印下template.raw，应该就知道了