In JavaScript, how can I increment a variable that is inside a function from the outside?

Question

I have tried declaring the variable outside the function but I get undefined.

      function scope() {
      let foo = 1;
      const bar = function() {
       return ++foo;
        }

        return bar;
        }

      const baz = scope();
      console.log(baz.foo);
      console.log(baz.foo);

You might want to make an object instead, see https://stackoverflow.com/questions/12610394/javascript-classes — Marco de Zeeuw, Sep 09 '17 at 10:48
@zer00ne `baz` would return the function `bar`, `console.log(baz());` would return the return-value of the function. — Marco de Zeeuw, Sep 09 '17 at 10:50

Dream_Cap · Answer 1 · 2017-09-09T11:05:14.893

1

Here is one way to do it, the Module pattern:

var Module = (function () {
//empty object
    var my = {};
//value
    my.value = 1;

  //method for incrementing the value 
    my.increment = function () {
        this.value++;
    };

    return my;
}());

Module.increment(); //increment the value from outside
console.log(Module.value) //log the new value

jsfiddle: https://jsfiddle.net/9dr9xy23/5/

edited Sep 09 '17 at 11:05

answered Sep 09 '17 at 10:55

Dream_Cap

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Good answer, but in your fiddle, `Module.moduleProperty` needs to be changed to `Module.value`. – freginold Sep 09 '17 at 11:02

In JavaScript, how can I increment a variable that is inside a function from the outside?

1 Answers1