console 命令行工具 X clear

> function a(){}
> 123
> 123
> function b(){}
> 123

console

function fn(a){
    console.log(a)
    var a = 123
    console.log(a)
    function a(){}
    console.log(a)
    var b = function b(){}
    console.log(b)
    console.log(a)
}
fn(1)