//今年才18
let myAge:number = 18;
let array2:number;
//转眼10年过去
myAge = myAge + 10;
let a:number;
let b:number;
a = 11;
b = 10;
myAge = b = a;
println("myAge is: ");
println(myAge); // 这里报错 return arg.toString(); TypeError: Cannot read property 'toString' of undefined