JSFiddle - React, Tailwind, and code Playground

HTML

<script>
    $(document).ready(function() {
        var p = new Parser();
        p.init();
        p.getArray();
        p.getArray2();
    }
</script>

JavaScript

function Parser() {

    var myArray = [];
    this.myArray2 = [];
    thisReference = this;
    this.myArray3=[];

    return {
        init: function () {
            alert("huhu");
            this.parse2();
            parse();
        },
        getArray: function () {
            alert(thisReference.myArray2.length);

        },
        getArray2: function () {
            alert(myArray);
        }
    }

    function parse() {
        var arr = [1, 2, 3];
        myArray.push(arr);
        myArray2.push(arr);
        
      for(var i =0;i<10;i++){
            a.push(i);
            thisReference.myArray3.push(a);
        }

    }
}
Parser.prototype.parse2 = function () {
    var arr = [1, 2, 3];
    myArray.push(arr);
    this.myArray2.push(arr);
};