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JavaScript Object-Oriented JavaScript (2015) Introduction to Methods Modifying Objects with Methods

Posted by joseph arias
joseph arias
9,269 Points

Uncaught TypeError: calculator.add is not a function

What am I doing wrong? 

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

    },
    clear: function() {
      this.sum = 0;

    }, 
    equals: function() {
      return this.sum;

    }
}
joseph arias
joseph arias
9,269 Points

ignore the script tags. I only posted it there to preview the Syntax highlighting

miikis
miikis
44,957 Points

Can you provide the code where you're calling Calculator.add()?

1 Answer

Steven Parker
Steven Parker
231,275 Points
Steven Parker
Steven Parker
231,275 Points

:point_right: I don't see any problem.

I tried this code and got a "32" displayed in the console:

calculator.clear();
calculator.add(21);
calculator.add(11);
console.log(calculator.equals());

I think Mikis is on the right track — it must be something odd where you call it.

One other thing to consider, unlike function definitions, object assignments are not "hoisted". So if you tried to call this function before the definition, it would fail.