If the player tries to consult our History Book about something for which we've defined no response, we need an appropriate message to be displayed. We use a DefaultConsultTopic for this purpose (just as we use other DefaultTopic types in conversation).
An appropriate DefaultConsultTopic is not hard to define. Since a book is an inanimate object, we don't need to vary its behaviour, and something simple like the following should suffice:
+ DefaultConsultTopic
"The book doesn't seem to have anything useful to say on that subject. "
;
If you wanted to make this a bit more sophisticated by suggesting to the player the topics that are available to be listed in the book, you could add a name property to each ConsultTopic you want suggested (e.g. name = 'Benedict' or name='the museum') and then expand the DefaultConsultTopic thus:
+ DefaultConsultTopic
"The book doesn't seem to have anything useful to say on that subject,
but a quick look in the index suggests that you could consult it
about <<suggestionList>>. "
suggestionList()
{
local lst = [];
foreach(local cur in location.consultTopics)
if(cur.name != nil)
lst += cur.name;
stringLister.showSimpleList(lst);
// n.b., not in the library but a custom object defined above
}
;
There are both advantages and disadvantages to this approach. On the one hand the player is not left to guess which topics the book implements; on the other, the message is a bit directive and may make consulting the book feel like working through the list of topics suggested.
A less directive approach, which may provide the best compromise, could be to provide the book with an index topic and drop a broad hint in the DefaultConsultTopic that there is an index to be consulted:
+ ConsultTopic @tIndex
"A quick look in the index suggests that you could consult it
about <<suggestionList>>. "
suggestionList()
{
local lst = [];
foreach(local cur in location.consultTopics)
if(cur.name != nil)
lst += cur.name;
stringLister.showList(lst);
}
;
+ DefaultConsultTopic
"So far as you can tell from the index, the book doesn't seem to
have anything useful to say on that subject. "
;
tIndex : Topic 'index/contents';
If you had several books in your game that you wanted to provide with an index you could avoid repetitive coding by defining an IndexTopic class:
class IndexTopic : ConsultTopic
suggestionList()
{
local lst = [];
foreach(local cur in location.consultTopics)
if(cur.name != nil)
lst += cur.name;
stringLister.showList(lst);
}
;