/**
* This method appends the specified object to this object's string.
*
* @access public
* @static
* @param IString\Type $xs the left operand
* @param IChar\Type $y the object to be appended
* @return IString\Type the string
*/
public static function append(IString\Type $xs, IChar\Type $y) : IString\Type
{
return IString\Type::box($xs->unbox() . $y->unbox());
}
/**
* This method returns whether this character is an upper case character.
*
* @access public
* @static
* @param IChar\Type $x the character to be evaluated
* @return IBool\Type whether this is an upper case
* character
*
* @see http://php.net/manual/en/function.ctype-upper.php
*/
public static function isUpperCase(IChar\Type $x) : IBool\Type
{
return IBool\Type::box(ctype_upper($x->unbox()));
}
