It is almost always undesirable from a user interface perspective to ask for help disambiguating a topic phrase. In the first place, since all topics tend to be in scope all the time, we might reveal too much about the inner model of the story if we were to enumerate all of the topic matches to a phrase. In the second place, topics are used in conversational contexts, so it almost never make sense for the parser to ask for clarification - the other member of the conversation might ask, but not the parser. So, we’ll always filter the list to the required number, even if it means we choose arbitrarily.

As a first cut, we prefer objects that are physically in scope to those not in scope: if the player is standing next to a control panel and types “ask bob about control panel,” it makes little sense to consider any other control panels in the simulation.

As a second cut, we’ll ask the actor to filter the list. Games that keep track of the actor’s knowledge can use this to filter according to topics the actor is likely to know about.

filterPluralPhrase (lst, np)OVERRIDDEN

action.t[6503]

filter a plural

filterPossRank (lst, num)OVERRIDDEN

action.t[6431]

Filter an ambiguous noun phrase list using the strength of possessive qualification, if any. For a topic phrase, we want to keep all of the possibilities.

getAll (np)OVERRIDDEN

action.t[6527]

we don’t allow ALL or provide defaults

getAllDefaults ( )OVERRIDDEN

action.t[6528]

no description available

getDefaultObject (np)OVERRIDDEN

action.t[6515]

get a default object

getPossessiveResolver ( )OVERRIDDEN

action.t[6389]

no description available

getQualifierResolver ( )OVERRIDDEN

action.t[6388]

get our qualifier resolver

noMatch (action, txt)

action.t[6523]

no description available

noMatchPoss (action, txt)

action.t[6524]

no description available

noVocabMatch (action, txt)

action.t[6522]

it’s fine not to match a topic phrase

objInPhysicalScope (obj)

action.t[6417]

Determine if an object is in physical scope. We’ll accept anything that’s in physical scope, and we’ll also accept any topic object that the actor knows about.

Note that this isn’t part of the basic Resolver interface. It’s instead provided as a service routine for our subclasses, so that they can easily determine the physical scope of an object if needed.

objInScope (obj)OVERRIDDEN

action.t[6399]

Determine if the object is in scope. We consider any vocabulary match to be in scope for the purposes of a topic phrase, since the subject matter of topics is mere references to things, not the things themselves; we can, for example, ASK ABOUT things that aren’t physically present, or even about completely abstract ideas.

packageTopicList (lst, match)

action.t[6365]

package a resolved topic list - if it’s not already represented as a ResolvedTopic object, we’ll apply that wrapping

resetResolver ( )OVERRIDDEN

action.t[6352]

remember the resolver for qualifier phrases

resolveTopic (lst, requiredNum, np)

action.t[6478]

Resolve the topic phrase. This returns a ResolvedTopic object encapsulating the resolution of the phrase.

This default base class implementation simply creates a resolved topic list with the whole set of possible matches undifferentiated. Subclasses for specialized actions might want to differentiate the items in the list, based on things like the actor’s knowledge so far or what’s in physical scope.

resolveUnknownNounPhrase (tokList)OVERRIDDEN

action.t[6489]

Resolve an unknown phrase. We allow unknown words to be used in topics; we simply return a ResolvedTopic that doesn’t refer to any simulation objects at all.

TADS 3 Library Manual
Generated on 5/16/2013 from TADS version 3.1.3