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HTML

              
                <pre id="output"></pre>
              
            
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CSS

              
                
              
            
!

JS

              
                //makes all objects iterable just like Maps!!! YAY
//iterates over Object.keys() (which already ignores prototype chain for us)
Object.prototype[Symbol.iterator] = function() {
    var keys = Object.keys(this)[Symbol.iterator]();
    var obj = this;
    var output;
    return {next:function() {
        if (!(output = keys.next()).done)
            output.value = [output.value, obj[output.value]];
        return output;
    }};
};

Object.prototype.something = 'bob';

var ordinaryObject = {well:'hello', there:'!'};
//true Maps are just cumbersome to create
var trueMap = new Map([['well', 'hello'], ['there', '!']]);
//now that object is iterable we can create a real Map from it
var realMap = new Map(ordinaryObject);

var buf = '';
function output(string, indent) {
	if (indent)
  	buf += '\t';
  buf += string;
  buf += '\n';
}

//problematic because it enumerates over prototypes
output('for in ordinary');
for (var name in ordinaryObject)
	output(name + ':' + ordinaryObject[name], true);
output('');

output('for of Map');
for (let pair of trueMap)
	output(pair[0] + ':' + pair[1], true);
output('fancier');
for (let [key, value] of trueMap)
	output(key + ':' + value, true);
output('');

//MAGIC! yay!
output('for of ordinary with patch');
for (let pair of ordinaryObject)
	output(pair[0] + ':' + pair[1], true);
output('fancier');
for (let [key, value] of ordinaryObject)
	output(key + ':' + value, true);
output('');

//just to prove you can create real maps from it if you felt like it
output('for of Map constructed with ordinary notation');
for (let pair of realMap)
	output(pair[0] + ':' + pair[1], true);
output('fancier');
for (let [key, value] of realMap)
	output(key + ':' + value, true);
output('');

//apparently you can just do this, though
output('for of ordinary\'s keys');
for (let key of Object.keys(ordinaryObject))
	output(key + ':' + ordinaryObject[key], true);
output('');



output('\n\n');



//note that maps force you to use .get() instead of [] notation
//outside of iterating, which is also annoying
output(trueMap.get('well'));
//but we get the best of both worlds with my way
//(well, asside from how inefficient the iterator creation is, but if you're really making maps to iterate A LOT you're probably doing something wrong)
output(ordinaryObject['well']);

document.getElementById('output').innerHTML = buf;
              
            
!
999px

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