/* Some form validation helpers
 */

function string_is_empty(val) {
  val = jQuery.trim(val);
  if (val == '') {
    return true;
  }
  return false;
}
function string_is_not_empty(val) {return !string_is_empty(val);}

function email_is_valid(val) {
  // http://ntt.cc/2008/05/10/over-10-useful-javascript-regular-expression-functions-to-improve-your-web-applications-efficiency.html
  var isEmail_re = /^\s*[\w\-\+_]+(\.[\w\-\+_]+)*\@[\w\-\+_]+\.[\w\-\+_]+(\.[\w\-\+_]+)*\s*$/;
  return String(val).search(isEmail_re) != -1;
}
function email_is_not_valid(val) {return !email_is_valid(val);}