【01】用构造器创建函数中的小知识
魔芋：在看ES5.1标准文档时。
Function (p1, p2, … , pn, body)
NOTE It is permissible but not necessary to have one argument for each formal parameter to be specified. For example, all three of the following expressions produce the same result:
（为每个形参指定一个参数是允许的，但没必要。例如以下三个表达式产生相同的结果：）
new Function("a", "b", "c", "return a+b+c")
new Function("a, b, c", "return a+b+c")
new Function("a,b", "c", "return a+b+c")
魔芋：例子：
var funa = new Function("a", "b", "c", "return a+b+c");
var funb = new Function("a, b, c", "return a+b+c");
var func = new Function("a,b", "c", "return a+b+c");
console.log(funa(1, 2, 3), funb(1, 2, 3), func(1, 2, 3));
var a= "moyu";
var funa = new Function(a, "b", "c", "return a+b+c");
/* function funa(moyu,b,c){
return a+b+c;
}
*/
var funb = new Function("a, b, c", "return a+b+c");
var func = new Function("a,b", "c", "return a+b+c");
console.log(funa(1, 2, 3), funb(1, 2, 3), func(1, 2, 3));
**