读javascript高级程序设计03-函数表达式、闭包、私有变量

test();
function test(){
alert(1);
}

test(); // test is not a function
var test=function(){
alert(1);
}

function f(num){
  if(num==1){
  return 1;
  }else{
  return num*f(num-1);
  }
}
console.log(f(4));//24
console.log(f(5));//120

var test=f;
f=null;
console.log(test(3));//报错， f is not a function

function f(num){
  if(num==1){
  return 1;
  }else{
  return num*arguments.callee(num-1);
  }
}
console.log(f(4));//24
console.log(f(5));//120
var test=f;
f=null;
console.log(test(3));//6

'caller', 'callee', and 'arguments' properties may not be accessed on strict mode functions or the arguments objects for calls to them

"use strict";
var f=function t(num){
if(num==1){
  return 1;
  }else{
  return num*t(num-1);
  }
}
console.log(f(4));//24
console.log(f(5));//120
var test=f;
f=null;
console.log(test(3));//6

function createFunctions(){
  var result=new Array();
  for(var i=0;i<10;i++){
    result[i]=function(){
    return i;
    }
  }
  return result;
}
var result=createFunctions();
result[1]();//10

function createFunctions(){
  var result=new Array();
  for(var i=0;i<10;i++){
    result[i]=(function(num){
    return num;
    })(i);
  }
  return result;
}
var result=createFunctions();
result[2];//2

var name='window';
var object={
  name:"object",
  getName:function(){
    return function(){
        return this.name;
    }
} 
};
object.getName()();//window

var name='window';
var object={
  name:"object",
  getName:function(){
var that=this;
     return function(){      
        return that.name;
    }
} 
};
object.getName()();//object