maximilian-krauss/dynamo.html

## dynamo.html
<!DOCTYPE html>
<html>
  <head>
  </head>
  <body>
    <script>

      var dynamo = function(obj, path, value) {
        if(obj === undefined || path === undefined) {
          return undefined;
        }

        var pathSegments = path.split('.'),
            write = (value !== undefined),
            isPrimitive = function(o) {
              return ['string', 'number', 'boolean'].indexOf(typeof o) > -1;
            };

        if(pathSegments.length === 1) {
          if(write) {
            obj[pathSegments[0]] = value;
          }

          return obj[pathSegments[0]];
        }

        var nextUp = pathSegments[0];

        if(write && !obj.hasOwnProperty(nextUp) || (write && isPrimitive(obj[nextUp]))) {
          obj[nextUp] = {};
        }

        if(obj.hasOwnProperty(nextUp)) {
          return dynamo( obj[nextUp], pathSegments.splice(1).join('.'), value );
        }

        return undefined;
      };

      var x = {
        a: {
          b: {
            c: {
              d: 1
            }
          }
        }
      };

      console.log(dynamo(x, 'a.b.c.d'));
      console.log(dynamo(x, 'a.b.c'));
      console.log(dynamo(x, 'a.b.c'));
      console.log(dynamo(x, 'b'));
      console.log(dynamo(x, '1'));
      console.log(dynamo(x, 'd.e.f', 2));
      console.log(dynamo(x, 'a.b.c.d.e.f.g.h.i.j.k.l.m', { x: { y: { z: 3 } } }));
      console.log(x);
    </script>
  </body>
</html>
	<!DOCTYPE html>
	<html>
	<head>
	</head>
	<body>
	<script>

	var dynamo = function(obj, path, value) {
	if(obj === undefined \|\| path === undefined) {
	return undefined;
	}

	var pathSegments = path.split('.'),
	write = (value !== undefined),
	isPrimitive = function(o) {
	return ['string', 'number', 'boolean'].indexOf(typeof o) > -1;
	};

	if(pathSegments.length === 1) {
	if(write) {
	obj[pathSegments[0]] = value;
	}

	return obj[pathSegments[0]];
	}

	var nextUp = pathSegments[0];

	if(write && !obj.hasOwnProperty(nextUp) \|\| (write && isPrimitive(obj[nextUp]))) {
	obj[nextUp] = {};
	}

	if(obj.hasOwnProperty(nextUp)) {
	return dynamo( obj[nextUp], pathSegments.splice(1).join('.'), value );
	}

	return undefined;
	};

	var x = {
	a: {
	b: {
	c: {
	d: 1
	}
	}
	}
	};

	console.log(dynamo(x, 'a.b.c.d'));
	console.log(dynamo(x, 'a.b.c'));
	console.log(dynamo(x, 'a.b.c'));
	console.log(dynamo(x, 'b'));
	console.log(dynamo(x, '1'));
	console.log(dynamo(x, 'd.e.f', 2));
	console.log(dynamo(x, 'a.b.c.d.e.f.g.h.i.j.k.l.m', { x: { y: { z: 3 } } }));
	console.log(x);
	</script>
	</body>
	</html>