javascript

1、

function a(){  var n = 0;  function inc() {    n++; // 获得了父函数的变量n    console.log(n);  }  inc();   inc(); }a(); //调用a, 控制台输出1，再输出2

2、

function a(){  var n = 0;  this.inc = function () {    n++;     console.log(n);  };}var c = new a();c.inc();  //输出1c.inc();  //输出2

3、

function a(){  var n = 0;  function inc(){    n++;     console.log(n);  }  return inc;}var c = a();c();  //控制台输出1c();  //控制台输出2

4、(和3好像没什么区别

function a(){  var n = 0;  var inc = function() {    n++;    document.writeln(n);  }   return inc;}var c = new a();c(); c();

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