Nodejs Number Add add(n)

Method Source Code

// Description://  www  . ja v  a  2 s.co m

// Method chaining is a very interesting way to keep your program clean.

// As a part of this Kata, you need to create functions such that one could evaluate the following expression:

// (3).add(5).multiply(2)
// The above expression evaluates to be 16.

// You need to implement the following methods:

// add
// subtract
// multiply
// divide
// square
// After you're done, one could chain these five methods to create chains of almost any length.


// mine
Number.prototype.add = function(n){
  return this+n
}
Number.prototype.subtract = function(n){
  return this-n
}
Number.prototype.multiply = function(n){
  return this*n
}
Number.prototype.divide = function(n){
  return this/n
}
Number.prototype.square = function(n){
  var _ = this;
  return Math.pow(_,2)
}


// top vote solution
Number.prototype.add      = function(n){ return this+n }
Number.prototype.subtract = function(n){ return this-n }
Number.prototype.multiply = function(n){ return this*n }
Number.prototype.divide   = function(n){ return this/n }
Number.prototype.square   = function(){ return this*this }

Related

1. add()

   Number.prototype.add = function () {
       return this + [].slice.apply(arguments).reduce(function (a, b) {
               "use strict";
               return a + b;
           },0);
   

2. add(a)

   Number.prototype.add = function(a) {
     return this.valueOf() + a;
   };
   Number.prototype.subtract = function(a) {
     return this.valueOf() - a;
   };
   Number.prototype.multiply = function(a) {
     return this.valueOf() * a;
   };
   ...
   

3. add(arg)

   Number.prototype.add = function(arg){
     var r1, r2, m;
     try{r1 = this.toString().split(".")[1].length}catch(e){r1=0}
     try{r2 = arg.toString().split(".")[1].length}catch(e){r2=0}
     m = Math.pow(10, Math.max(r1, r2))
     return (this*m+arg*m)/m
   Number.prototype.sub = function(arg){
     return this.add(-arg)
   ...
   

4. add(n) return this+n }

   Number.prototype.add      = function(n){ return this+n }
   Number.prototype.subtract = function(n){ return this-n }
   Number.prototype.multiply = function(n){ return this*n }
   Number.prototype.divide   = function(n){ return this/n }
   Number.prototype.square   = function(){ return this*this }
   

5. add(num)

   Number.prototype.add = function(num) {
     return this + num;
   var n = 5;
   assert(n.add(3) == 8, 'It works when the number is in a variable.');
   assert((5).add(3) == 8, 'Also works if a number is wrapped in parentheses.');
   assert(5.add(3) == 8, 'What about a simple literal?');
   

6. add(num)

   Number.prototype.add = function(num)
       return this+num;
   };
   describe("6.13", function () {
       it("It works when the number is in a variable.", function () {
            expect(n.add(3)).toEqual(8);
       });
       it("It works when the number is in a parentheses.", function () {
   ...
   

7. add(num)

   Number.prototype.add = function (num) {
     return this + num;
   };
   Number.prototype.subtract = function (num) {
     return this - num;
   };
   Number.prototype.multiply = function (num) {
     return this * num;
   };
   ...