keyPair_fromSecretKey static method
Implementation
static KeyPair keyPair_fromSecretKey(Uint8List secretKey) {
  KeyPair kp = KeyPair(publicKeyLength, secretKeyLength);
  Uint8List pk = kp.publicKey;
  Uint8List sk = kp.secretKey;
  // copy sk
  for (int i = 0; i < kp.secretKey.length; i++) sk[i] = secretKey[i];
  // copy pk from sk
  for (int i = 0; i < kp.publicKey.length; i++)
    pk[i] = secretKey[32 + i]; // hard-copy
  return kp;
}