public function testReplace()
{
$this->eq(s::replace('abcxabc', 'x', 'y'), 'abcyabc');
$this->eq(s::replace('afoobara', 'foobar', 'b'), 'aba');
$this->eq(s::replace('aaxyaaaxya', 'xy', 'b'), 'aabaaaba');
$this->eq(s::replace('', 'abc', ''), '');
$this->eq(s::replace('abc', '', 'x'), 'xaxbxcx');
$this->eq(s::replace('', '', 'x'), 'x');
}
public function iReplace($old, $new)
{
return new self(s::replace($this->value, self::unwrap($old), self::unwrap($new)));
}