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

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 145,858 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:

That was a great explanation, thanks so much!