Calling a prototype method while preserving state

Question

I'm having trouble making a recursive call in this prototype method. The console prints:

count 1 (index):30
Uncaught ReferenceError: count is not defined

Instead, I need it to print:

count 1 (index):30
count 2 (index):30

...

var MyClass, mc;

MyClass = (function() {
  function MyClass() {
    this.count = 1;
  }

  MyClass.prototype.method = function() {
    console.log("count", this.count);
    this.count++;
    if (count === 2) {
      method();
    }
  };

  return MyClass;

})();

mc = new MyClass();

mc.method();

http://jsfiddle.net/audfmotf/

More on prototype and constructor functions here: http://stackoverflow.com/questions/16063394/prototypical-inheritance-writing-up/16063711#16063711 — HMR, Oct 16 '14 at 02:55

score 1 · Accepted Answer · answered Oct 15 '14 at 21:01

1

You forgot a couple of this inside method.

MyClass.prototype.method = function() {
  console.log("count", this.count);
  this.count++;
  if (this.count === 2) {
    this.method();
  }
};

answered Oct 15 '14 at 21:01

berrberr

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score 0 · Answer 2 · answered Oct 15 '14 at 21:01

0

count is not the same as this.count. Your condition checks for an undefined variable, instead of:

if (this.count === 2) {
      this.method();
    }

answered Oct 15 '14 at 21:01

Shomz

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Calling a prototype method while preserving state

2 Answers2