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

Hamed Ali
Hamed Ali
5,626 Points
Posted by Hamed Ali
Hamed Ali
5,626 Points

Does anyone know what I am doing wrong with this subtract method here?

Does anyone know what I am doing wrong with this subtract method here?

calculator.js 
var calculator = {
  sum: 0,
  add: function(value) {
    this.sum += value;
  },

  sum: 0,
  subtract: function(value) {
      this.subtract -= value;
  },

  multiply: function(value) {

  },
  divide: function(value) {

  },
  clear: function() {     // clears the screen
    this.sum = 0;
  }, 
  equals: function() {    //returns the sum
    return this.sum;
  }
}

1 Answer

Vittorio Somaschini
Vittorio Somaschini
33,371 Points
Vittorio Somaschini
Vittorio Somaschini
33,371 Points

Hello Hamed.

You do not have to use subtract but still have to use sum, so:

this.sum -= value

Hope this helps