1 var Pagination = (function() { 2     var _default_limit = 1; 3     var isArray = Array.isArray || function(arr) { 4         return {}.toString.call(arr) == '[object Array]'; 5     }; 6  7     var isInt = function(x) { 8         var type = typeof x; 9         return type !== null && (type === 'number');10     }11 12     function _Pagination(list, limit) {13         if (!(this instanceof Pagination)) {14             return new Pagination(list, limit || _default_limit);15         }16         if (!isArray(list)) throw new Error("list must be array");17         this.list = list;18         this.limit = limit;19         this.total = Math.ceil(list.length / limit);20         return this;21     }22 23     _Pagination.prototype.page = function(pagenum) {24         if (!isInt(pagenum)) throw new Error("pagenum must be number");25         if (pagenum < 1 || pagenum > this.total) {26             throw new Error("pagenum must be in range[" + 1 + ", " + this.total + "]");27         }28         var start = this.limit * (pagenum - 1);29         return this.list.slice(start, start + this.limit);30     };31 32     _Pagination.prototype.toString = function() {33         var result = [];34         for (var i = 1; i <= this.total; i++) {35             result.push("[" + this.page(i).join(',') + "]");36         }37         return result.join(',');38     }39     return _Pagination;40 41 })();42 43 var pagination = Pagination([1, 32, 43, 4, 15, 6, 7, 8, 9, 10,34],2);44 console.log(pagination+"")