/**
* @param PrivateKeyInterface $privateKey
* @param int|string $integer
* @return \BitWasp\Bitcoin\Key\PrivateKey
* @throws \Exception
*/
public function privateKeyAdd(PrivateKeyInterface $privateKey, $integer)
{
$privKey = $privateKey->getBuffer()->getBinary();
// mod by reference
$ret = (bool) \secp256k1_ec_privkey_tweak_add($privKey, $this->getBinaryScalar($integer));
if ($ret === false) {
throw new \Exception('Secp256k1 privkey tweak add: failed');
}
return $this->getRelatedPrivateKey($privateKey, $privKey);
}
