return \
strlen($string) === \
strlen($this->string
) && 0 ===
mb_stripos($this->string,
$string, 0, 'UTF-8'
);
} return $string ===
$this->string;
} public function indexOf(string|iterable|AbstractString
$needle, int
$offset = 0
): ?int
{ if ($needle instanceof AbstractString
) { $needle =
$needle->string;
} elseif (!\
is_string($needle)) { return parent::
indexOf($needle,
$offset);
} $form = null ===
$this->ignoreCase ? \Normalizer::NFD : \Normalizer::NFC;
normalizer_is_normalized($needle,
$form) ?:
$needle =
normalizer_normalize($needle,
$form);
if ('' ===
$needle || false ===
$needle) { return null;
} try { $i =
$this->ignoreCase ?
grapheme_stripos($this->string,
$needle,
$offset) :
grapheme_strpos($this->string,
$needle,
$offset);
}