JavaScript works behind the scenes —— hoisting and TDZ(变量提升和暂时性死区)

concept

Makes some types of variables accessible/usable in the code before they are actually declared. "Variables lifted to the top of their scope"

(让某些类型的变量可以在他们被真正声明之前就可以使用，将他们提升到最高层的作用域)

how to hoisting?

TDZ(Temporal dead zone)(暂时性死区)

变量用let/const声明之前就调用，那时不可用，在声明之前的scope成为暂时性死区。

example：

console.log(`Hello ${name}`)
let name = 'kihyun'

throw error: Reference Error: Cannot access 'name' before initialization