Preserving Variable State Across Restart / Restore

Authoring Inform 6
1

Greetings all! I’m having trouble figuring out how to do something. I’m trying to have a case where the player can be sent back in time. But this will mean essentially a “restart” of the game. Some dialogue, however, will indicate that they did, in fact, have a “world reset.” So I need to preserve a state that says such a reset happened.

Here’s what I’m trying. (Incredibly minimal experiment.)

!% -G
!% +include_path=../../inform6lib

Constant Story "Learning";
Constant Headline "^An Interactive Learning Example^";

Include "Parser";
Include "VerbLib";

Constant RESET 1;

Array time_travel_state -> 2;

[ Initialise;
  print time_travel_state -> 1;
  TimeTravelOccurred();

  if (time_travel_state -> RESET == false) {
    print "Time travel has not occurred.";
  } else {
    print "Time travel has occurred.";
  }
];

[ TimeTravelOccurred;
  @protect time_travel_state 1;
];

Include "Grammar";

[ MyResetSub;
  time_travel_state -> RESET = true;
  TimeTravelOccurred();
  print time_travel_state -> 1;
];

Extend "version" replace
* -> MyReset;

end;

For this simple example, if someone types “VERSION”, I’ve set up a replace function that will set the variable in question to true. Then I have a TimeTravelOccurred state that will protect that variable.

What I’m doing definitely doesn’t work. Meaning that even if I just do a restart, nothing actually gets protected. I’m also going to clearly need this to persist across save/restore, but if my small experiment on restart isn’t workable, there’s probably not much point in complicating the example.

Does what I’m doing here seem logical at all?

2

Note: This is for Glux. I didn’t know, and had to google @protect.

You ask to protect one byte of memory, and then you only access the second byte from the start of the array. So no, it’s not protected.

3

AH! So simple and you are correct indeed. For some reason, I was reading @protect as protecting the one part I wanted, not the whole thing. Which was a silly oversight on my part. So I changed my statement in TimeTravelOccurred to:

@protect time_travel_state 2;

That did the trick! Much thanks. So that works if there’s a restart in game. Obviously if a game starts up totally new, the default is retained, which makes sense, and is desired. So now I just have to make sure to handle a restore action.

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