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JavaScript Object-Oriented JavaScript (2015) Introduction to Methods Finishing the Calculator

Brittany Smith
Brittany Smith
8,046 Points
Posted by Brittany Smith
Brittany Smith
8,046 Points

implement the subtract function: am I overthinking this?

I can't help but assume I'm over thinking this. I tried just changing the + at the top to a - and it told me to stop cheating? The videos before this have been about using this. but I must be missing a step?

calculator.js 
var calculator = {
  sum: 0,
  add: function(value) {
    this.sum += value;
  },
  subtract: function(value) {
  this.subtract 
  },
  multiply: function(value) {
  this.multiply
  },
  divide: function(value) {
  this.divide
  },
  clear: function() {
    this.sum = 0;
  }, 
  equals: function() {
    return this.sum;
  }
}

1 Answer

Jason Anders
MOD
Jason Anders
Treehouse Moderator 145,860 Points
Jason Anders
Jason Anders
Treehouse Moderator 145,860 Points

Hey Brittany,

You may be 'misthinking' the challenge. You shouldn't be changing the + because that is part of the add method and needs to be a + sign. Task 1 wants you to add the code to make the subtract method work, Task 2 the multiply ... and so forth.

var calculator = {
  sum: 0,
  add: function(value) {
    this.sum += value;
  },
  subtract: function(value) {
    // Task one code goes here
  },
  multiply: function(value) {
    // Task two code goes here
  },
  divide: function(value) {
    // Task three code goes here
  },
  clear: function() {
    this.sum = 0;
  }, 
  equals: function() {
    return this.sum;
  }
}

The code would be the same as the add method, but with the respective math symbols for the associated methods.

Hope that helps :)

Keep Coding! :dizzy:

Valeriia O
Valeriia O
Courses Plus Student 17,625 Points

That was a great explanation, thanks so much!