Suppose I have a tree in a garden, and the tree can be climbed. When in the garden the player can type CLIMB, CLIMB TREE, CLIMB UP or just UP to ascend the tree.
Once in the tree, the player can do CLIMB DOWN or just DOWN to get back down. Would you also expect to be able to do CLIMB or CLIMB TREE to go down the tree?
If not, how should the parser respond?
If so, what about if you can climb higher up the tree? Does CLIMB take you up or down?
I suspect youâll get player variance on this topic.
Personally I treat verbs like this as toggles. A cliff has two ends. CLIMB at either end will take you to the other. Ditto ladders and other two-ended things. Or a bridge and CROSS. I guess I feel if I do implement things this way, Iâve covered people who think like me, and people who donât wonât be affected.
(Okay, so it might get more complicated if you have a three storey tree 
)
-Wade
well, the extreme case ought to be an âAnnoytron II: Climbing the sequoiaâ⌠
Best regards from Italy,
dott. Piergiorgio.
Agreed.
If you are at the top of the tree, yes.
If you are midway up a tree, then CLIMB UP and UP should take you up the tree, CLIMB DOWN and DOWN should take you down the tree, CLIMB and CLIMB TREE are ambiguous, so the game should ask whether you want to go up or down.
Thanks for the comments so far. Another one. Would anyone every CLIMB DOWN STAIRS or CLIMB STAIRS to go down the stairs? I think CLIMB STAIRS to go up them is possible.
I canât recall whether Iâve ever used CLIMB UP STAIRS or CLIMB DOWN STAIRS, but I donât think itâs unreasonable. If you added this to the climb tree scenario, then everything thatâs valid for the climb tree scenario is also valid for the climb stairs scenario.
EDIT: In fact, I have used CLIMB UP <noun> and CLIMB DOWN <noun> in at least one of my own games.
CLIMB STAIRS works to go both up and down stairs, in Inform, if you build the stairs in the âobviousâ way. (Create an always-open door object called âstairsâ between the rooms.) I recommend keeping that behavior because somebody might be used to it.
CLIMB UP/DOWN STAIRS seems like a nice thing to support, but I donât think Iâve ever used it. I think people are more likely to type CLIMB UP/DOWN, with no noun, just because thatâs shorter! So if you go down (or up) this route, be sure that works.
In the context of a parser game something short is good, and âclimbâ and âclimb treeâ would be useful for climbing down a tree. Maybe Iâm bad at English though because I generally associate âclimbâ with going up.
I think thatâs how most English speakers would mean it.
I was going to make the point that perhaps for a link based game it would be nice to specify the longer âclimb downâ, but I think Iâm satisfied with the shorter version for parsers. Or at least I canât think of a better alternative.
I agree. That was really why I asked the question.
But given the responses, sounds like CLIMB should be for going down as well. Thanks everyone.
The (likely idiosyncratic) connotations for one native speaker of American English:
âClimbâ implies exertion or effort or care. So you climb up a lot more things than you climb down, 'cause itâs not climbing down if itâs trivial. Certainly, one might climb down a rope, or a mountain, or a tree, or a ladder. Parents shout âClimb down from there!â as an imperative to kids who have gotten somewhere precarious.
But if the context is an able-bodied person going down a short set of stairs of modest slope, a reference to âclimbing downâ them would sound a little off.
You try being able-bodied and getting on in this life! -runs off in tears-
-Wade
I think the difference between stairs and trees is that itâs obvious that you can go UP/DOWN stairs, but itâs not obvious that the tree is there to climb, so if I was in a field with a big tree, I wouldnât automatically show UP as one of the exits. However, once someone had climbed the tree, the location to which theyâd go would have DOWN listed as an exit. I would also allow âCLIMB DOWNâ as a synonym for DOWN for any location the player had to climb up to reach.
I must admit, Iâd not even thought of using CLIMB STAIRS as a synonym for UP (or DOWN) in a location with stairs. Just as I donât tend to use GO THROUGH DOORWAY or CROSS FIELD (for example) as synonyms for moving between locations where the compass directions are already listed as exits.
I think thereâs a balance to be struck between trying to parse every way in which movement could be articulated and expecting a player to respond according to certain IF conventions (such as using compass directions/UP/DOWN/IN/OUT).