常见函数的4种类型（js的问题）

(function(a, b){
  console.log(a + b);}
)(1, 2);
 
 
// 等价于
function foo (a, b){
  console.log(a + b);
}
 
foo(1, 2);

(function(window, undefined){
  var jQuery;
  ...
  window.jQuery = window.$ = jQuery;
})(window);

var arr = [33, 9, 11, 6];
 
arr.sort(function (a, b) {
  return a - b;
});
 
console.log(arr);
// [6, 9, 11, 33]

function getPrice(params, callback){
  $.ajax({
    url: '/getPrice',
    type: 'POST',
    data: params,
    success: function(data){
      callback(data);
    }
  })
}

var func = function(x) {
  if(x === 2){
    return x
  } else{
    return x * f(x - 1)
  }
}

function func(x){
  if(x === 1){
    return 1
  } else{
    return x * arguments.callee(x -1)
  }
}

function Person(){} // 构造函数
 
new Person()
 
function person(){} // 方法