console.log(Math.random().toString(36).substring(2))
console.log(Math.random().toString(16).substring(2))
console.log(Math.random().toString(36).substring(2).length)
console.log(Math.random().toString(16).substring(2).length)

var ie = !-[1,];

console.log(ie);

console 命令行工具 X clear

console