JSFiddle - React, Tailwind, and code Playground

JavaScript

Object.prototype.reduce = function( reduceCallback, initialValue ) {
    var obj = this, keys = Object.keys( obj );

    return keys.reduce( function( prevVal, item, idx, arr ) {
        return reduceCallback( prevVal, item, obj[item], obj );
    }, initialValue );
};

var o = { foo: 1, bar: 2 };

for(var p in o)
    console.log(p);