Array.prototype.deleteRang = function (rang) {
	var l = this.length;
	for (i = rang;i < l-1;i++) 
		this[i] = this[i+1];
	this.pop();
	return true;
}

Array.prototype.push_isnot = function (elem) {
	var i = 0,rep = -1;
	while (this[i] && rep < 0) {
		if (this[i] === elem) rep = i;
		i++;
	}
	if (rep == -1) {
		rep = i;
		this.push(elem);
	}	
	return rep;
}

String.prototype.is_style = function () {
	var regle = /^([a-zA-Z-]{3,}:[a-zA-Z0-9 -=,:.#%()\/']+;)+$/;
	return regle.test(this);
}

String.prototype.is_class = function () {
	var regle = /^[a-zA-Z_]+$/;
	return regle.test(this);
}

String.prototype.RLtrim = function () {
	return this.replace(/(^\s*)|(\s*$)/g,"");
}