SymDoor

A Symmetrical Door is a door that can be traversed in either direction and exists in both the locations it connects. It behaves much like a regular Door, except that it uses only one object, not two, to represent the door. [SYMCOMM EXTENSION]

You'd typically use it by pointing the appropriate direction property of one room to point to it and then defining its room2 property as the room to which it leads, for example:

redRoom: Room 'Red Room'
"A door leads south. " *.
south = blackDoor
; *.
blackDoor: SymDoor 'black door'
"It's black. "
room2 = greenRoom
; *.
greenRoom: Room 'Green Room'
"A door leads north. "
;

Note that a Symdoor is a MultiLoc, so we don't use the + notation to set its location when defining it; it exists in both locations. The SYMCOMMN EXTENSION will automatically set the north property of room2 (here greenRoom) to point to the same door (here blackDoor).

Both sides of a SymDoor must have the same name ('black door' in the example above). You can, however, give the two sides of a SymDoor different descriptions if you wish by defining its room1Desc and room2Desc properties instead of its desc property (as you would expect, room1Desc and room2Desc will then be the descriptions of the door as seen from room1 and room2 respectively, where room1 and room2 have the same meaning as they have on a SymConnector). You can also give the two sides of the SymDoor different lockabilities by defining room1Lockability and room2Lockability separately. Alternatively, if you want both sides to have the same locking behaviour, just override the lockability property. The one thing you can't do (without some clever extra coding of your own) is to define different keys for each side of a SymDoor.

It's sometimes convenient to refer to a door by the direction it leads in (e.g. "The west door" or "The north door"). The symconn extension takes care of this for you automatically. For example, the black door in the example above can be referred to by the player as 'south door' when the player character is in redRoom and as 'north door' when the player character is greenRoom and the game will know which door is meant, without the game author having to take any steps to make this happen. If, however, you want to suppress this behaviour on a particular SymDoor, you can do so simply by overriding its attachDir property to nil (attachDir is a method that works out which direction property a SymDoor is attached to in the player character's location, which is used by the DirState State object to add the appropriate direction name adjectives, such as 'north', to the SymDoor's vocab).

class SymDoor : SymPassage