Array extensions in JavaScript

arrayExtensions.js

Array.prototype.where = function (query) {
	if (!query) {
		return this;
	}

	if (typeof(query) == 'function') {
		return this.filter(query);
	};

	return this.filter(function (e) {
		var result = true;

		for (var key in query) {
			var value = query[key];
			var elementValue = e[key];

			result = result && elementValue == value;
		}

		return result;
	});
}

Array.prototype.any = function (query) {
	var result = this.where(query);

	return result && result.length > 0;
}

Array.prototype.first = function (query) {
	var result = this.where(query);

	if (result && result.length > 0) {
		return result[0];
	}
}