Result<InputStream, FileNotFoundException> openFileStream(String filename) {
        try {
            return Result.ok(new FileInputStream(filename));
        } catch (FileNotFoundException e) {
            return Result.err(e);
        }
    }

    ...
    
    InputStream defaultStream = System.in;

    InputStream workWithStream = openFileStream("no such file").project(
            stream   -> stream,
            notFound -> defaultStream
    );

    openFileStream("no such file").handle(
            stream -> workWithStream(inputStream),
            err    -> System.out.println("Failed to open file " + err.getMessage())
    );

    openFileStream().toOptional()
            .map(stream -> extractInfoFromStream(stream))
            .ifPresent(System.out::println);
    
    
    ...

        public interface AuthenticationService {
            ...
    
            ResultTriple<Token, AuthenticationFailed, ServerConnectionFailed> signIn(String login, String password);
        }
 
 ...
 
        stubFor(postToLoginApi.willReturn(aResponse()
                .withFault(Fault.MALFORMED_RESPONSE_CHUNK)));

        assertTrue(
                authService.signIn("login", "password").project(
                        token                  -> false,
                        authenticationFailed   -> false,
                        serverConnectionFailed -> true)
        );
        
  ... 
 
        boolean isSuccessful = authService.signIn("login", "password").project(
                token -> {
                    assertEquals(token.getTokenString(), "test_token");
                    assertTrue(authService.isSignedIn());

                    return true;
                },
                authenticationFailed   -> false,
                serverConnectionFailed -> false
        );

        assertTrue(isSuccessful);