Element DOM parser. i18n

<input type="text" class="i18n" data-labels="value#str001 placeholder#str002" />
<button class="i18n" data-labels="innerText#str003">Click Me</button>
<div class="i18n" data-labels="innerText#str004">This string will never be translated</div>

<script>
  
function i18n_parse (rootElement, labelAttribute, iterator) {
	if (arguments.length === 1 && typeof arguments[0] === "function") {
		iterator 	= arguments[0];
		rootElement 	= null;
		labelAttribute 	= null;
	}

	if (arguments.length === 2 && (
		typeof arguments[0] === "object" &&
		typeof arguments[1] === "function")) {

		rootElement 		= arguments[0];
		iterator 		= arguments[1];
		labelAttribute 		= null;
	}

	if (iterator === undefined) { throw "An iterator must be specified"; }

	if (typeof labelAttribute !== "string") {
		labelAttribute = "data-labels";
	}

	if (window.jQuery && rootElement instanceof jQuery) {
		rootElement = rootElement.get(0);
	}

	if (rootElement == undefined) {
		rootElement = document;
	}

	var nodes = rootElement.querySelectorAll(".i18n");

	Array.prototype.forEach.call(nodes, function (node) {

		if ( node.hasAttribute(labelAttribute) ) {
			var a = node.getAttribute(labelAttribute);

			if (a.trim) { a = a.trim(); }
			var localStrings = a.split(" ");

			localStrings.forEach(function (localString) {
				var b 				= localString.split("#")
					,	attrName 	= b[0]
					,	stringName 	= b[1]
					,	stringValue = iterator(stringName);

				if (typeof stringValue !== "string") { stringValue = ""; }
				if (stringValue.trim) { stringName = stringName.trim(); }

				if ( stringValue && attrName.toLowerCase() == "innertext") {
					node.innerText = stringValue;
				}
				else if ( stringValue ) {
					node.setAttribute(attrName, stringValue);
				}
			});
		}

	});
}

// USAGE
var strings = {
	"str001": "John Doe",
	"str002": "Type your name...",
	"str003": "Click for Love",
	"str004": ""
};

i18n_parse(document, function (stringName) {
	return strings[stringName];
});
</script>