import 'package:ed25519_edwards/ed25519_edwards.dart' as ed;

    void signAndVerify() {
      var keyPair = ed.generateKey();
      var privateKey = keyPair.privateKey;
      var publicKey = keyPair.publicKey;
      var message = utf8.encode('test message');
      var sig = ed.sign(privateKey, message as Uint8List);
      var result = ed.verify(publicKey, message, sig);
      assert(result == true);
    
      var wrongMessage = utf8.encode('wrong message');
      var wrongResult = ed.verify(publicKey, wrongMessage as Uint8List, sig);
      assert(wrongResult == false);
    }