[TADS3] counting rooms visited

Authoring TADS
1

I have a coding problem:

basically, I need that the character (not the player) noticing, after visiting the first four or so locations, that something is off (a clue to the player) But I don’t figure how to count the number of rooms visited so far (perhaps the solution is hidden in the mare magnum of methods, properties, classes &c. ?)

Best regards from Italy,
dott. Piergiorgio.

2

Not tested, but shouldn’t afterTravel work? Like:

Bob: Actor 

visitedRoomTrail = []
afterTravel(traveler, connector) {

  inherited (traveler, connector);
  visitedRoomTrail += location;

  if(visitedRoomTrail.length>=4)
    "Bob makes a statement"

}
;
3

In adv3/travel.t, the BasicLocation class has this method:

/*
 *   Receive notification that a traveler is arriving.  This is a
 *   convenience method that rooms can override to carry out side
 *   effects of arrival.  This is called just before the room's
 *   arrival message (usually the location description) is displayed,
 *   so the method can make any adjustments to the room's status or
 *   contents needed for the arrival.  By default, we do nothing.
 */
enteringRoom(traveler) { }

You can create a special class for the locations that partake in room counting that inherits from one of the BasicLocation subclasses (like Room). Override enteringRoom(traveler) in that class to increase a global counter if traveler is the player character, and check if it’s >= 4 and if yes, run the clue code. Make all locations that should be affected by this be objects of that class.

4

Thanks to both !
Albeit Tomas’s idea is good, RealNC’s one looks better because follows TADS’s philosophy since 2.0, namely using modify/replace, hence my flagging RealNC’s reply as solution.

I’m sure that using appropriately enteringRoom and hasSeen/setHasSeen (the latter because I prefer avoid counting player’s backtracking; the obvious brute-force approach (checking and counting the trues of [room].hasSeen of the dozen or score of locations nearest the start location) is definitively NOT good coding…

Best regards from Italy,
dott. Piergiorgio.

5

Note that there’s no modify nor replace here. Just inheritance and overriding of inherited methods:

class MagicRoom: Room
{
    enteringRoom(traveler)
    {
        inherited(traveler); // just good practice for future-proofing
        if (traveler != gPlayerChar) {
            return;
        }
        ++travel_counter;
        if (travel_counter > 3) {
            // show clue
        }
    }
}

Locations affected by this should them be of class MagicRoom.

6

Thanks. After adding an AND check if is first time visited, is perfect for what I envision. On top of it, allows adding an AGT feature I sorely miss (the rooms discovered count in the score/quit)

Best regards from Italy,
dott. Piergiorgio.