Swift_Mime_SimpleMimeEntity::assertValidBoundary PHP Method

    private function assertValidBoundary($boundary)
    {
        if (!preg_match('/^[a-z0-9\'\\(\\)\\+_\\-,\\.\\/:=\\?\\ ]{0,69}[a-z0-9\'\\(\\)\\+_\\-,\\.\\/:=\\?]$/Di', $boundary)) {
            throw new Swift_RfcComplianceException('Mime boundary set is not RFC 2046 compliant.');
        }
    }