SOURCE

function sayHi(){
  console.log("Hello "+ arguments[0] +','+ arguments[1]);
}
sayHi('Jone','morning');

function howManyArgs(){
  console.log(arguments.length);
}
howManyArgs("string",45);
howManyArgs();
howManyArgs(12);
console 命令行工具 X clear

                    
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console