code: function (value, constraint) {
  
          if (valdrUtil.isEmpty(value)) {
            return true;
          }
          if (valdrUtil.isNaN(Number(value))) {
            return false;
          }
  
          return doValidate(value, constraint);
        }
docs: Checks if the value is a number within accepted range.
  
  @param value the value to validate
  @param constraint the validation constraint, it is expected to have integer and fraction properties (maximum
  number of integral/fractional digits accepted for this number)
  @returns {boolean} true if valid