function isValidUserName (name) {
	return /^\w+([\.-]?\w+)*$/.test (name);
}

function isValidFirstName (name) {
	return /^(\w\.|\w{2,})(\ (\w\.|\w{2,}))*$/.test (name);
}

function isValidLastName (name) {
	return /^(\w\')?\w{2,}((\ |\-|\ \-\ )((\w\')?\w{2,}))*$/.test (name);
}

function isValidEmail (email) {
	return /^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,})+$/.test (email);
}

function isEmpty (text) {
	return !/\S/.test (text);
}

/* */

function isEmptyField (field) {
	return !/\S/.test (field.value);
}

function isNotChecked(field) {
	if(!field.checked) 
		return true;
	return false;
}

function isNotInLimits(field,min,max) {
   	if (field.value.length<min || field.value.length>max) 
		return true;
	return false;
}