[solved] javascript: strange behavior // The problem that was that concat() dosen't change the value of the array, it returns the two arrays joined

gistfile1.js

function Foo(){
    this.baz = [];
    this.set = function(bar){
        this.baz = this.baz.join(bar);
        return this;
    }
}

foo = new Foo();
foo.set({'a':123}).set({'b':321});
console.log(foo.baz); 
// [ ] --empty