Collections\TypeValidator::determineType PHP Метод

    private function determineType($type, $keyType = false)
    {
        if (!$keyType && $this->nonScalarTypeExists($type)) {
            return $type;
        }
        if ($scalarType = $this->determineScalar($type)) {
            if ($keyType && in_array($scalarType, ["double", "boolean"])) {
                throw new InvalidArgumentException("This type is not supported as a key.");
            }
            return $scalarType;
        }
        throw new InvalidArgumentException("This type does not exist.");
    }