function writePkcs1(der, key) {
	der.startSequence();

	switch (key.type) {
	case 'rsa':
		if (PrivateKey.isPrivateKey(key))
			writePkcs1RSAPrivate(der, key);
		else
			writePkcs1RSAPublic(der, key);
		break;
	case 'dsa':
		if (PrivateKey.isPrivateKey(key))
			writePkcs1DSAPrivate(der, key);
		else
			writePkcs1DSAPublic(der, key);
		break;
	case 'ecdsa':
		if (PrivateKey.isPrivateKey(key))
			writePkcs1ECDSAPrivate(der, key);
		else
			writePkcs1ECDSAPublic(der, key);
		break;
	case 'ed25519':
		if (PrivateKey.isPrivateKey(key))
			writePkcs1EdDSAPrivate(der, key);
		else
			writePkcs1EdDSAPublic(der, key);
		break;
	default:
		throw (new Error('Unknown key algo: ' + key.type));
	}

	der.endSequence();
}
Define argument syntax for the top-level command.

@api public