Javascript Object or new function for function handler -

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i bit confused 1 of following right way create handler containing functions...an object function or new function itself? say, handler calculator functions...

calculatorhandler = new function(){     this.add = new function(a, b){           return + b;     };     this.sub = new function(a, b){           return a-b;     }; };

or

calculatorhandler = {     this.add: function(a, b){           return + b;     },     this.sub: function(a, b){           return a-b;     } };

are there advantage/disadvantage of 1 on other?

if want have "basket" hold functions together, use object, there no need constructor function:

calculatorhandler = {     add: function(a, b){           return + b;     },     sub: function(a, b){           return a-b;     } };

note how this in example incorrect refer scope define calculatorhandler object in (probably global - window).

on other hand if want build calculator have data , operations on it, can use oop-like approach in first example.

calculatorhandler = function() {   this.total=0;    this.add = function(a) {     this.total += a;   };    this.sub = function(a) {     this.total -= a;   }; }  var calc = new calculatorhandler(); calc.add(4); calc.sub(3);

and better solution, based on prototipal inheritance:

calculatorhandler = function() {   this.total=0; }  calculatorhandler.prototype.add = function(num) {   this.total += num; }  calculatorhandler.prototype.sub = function(num) {   this.total -= num; };  var calc = new calculatorhandler(); calc.add(4); calc.sub(3);

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