public function isSingular($string)
{
// Check cache assuming the string is plural.
$singular = isset($this->cache['singularized'][$string]) ? $this->cache['singularized'][$string] : null;
$plural = $singular && isset($this->cache['pluralized'][$singular]) ? $this->cache['pluralized'][$singular] : null;
if ($singular && $plural) {
return $plural != $string;
}
// If string is not in the cache, try to pluralize and singularize it.
return self::singularize(self::pluralize($string)) == $string;
}