implicitGroupTransform

Transcript Transform: group implicit announcements. We'll find any runs of consecutive implicit command announcements, and group each run into a single announcement listing all of the implied actions. For example, we'll turn this:

>go south
(first opening the door)
(first unlocking the door)

this into:

>go south
(first opening the door and unlocking the door)

In addition, if we find an implicit announcement in the middle of a set of regular command reports, and it's for an action nested within the action generating the regular reports, we'll start a new paragraph before the implicit announcement.

implicitGroupTransform : TranscriptTransform

no description available

Can we group the second item with the first? Returns true if the second item is also an implicit action announcement, or it's a default object announcement whose parent action is the first item's action.

Process default object announcements in a grouped message vector.

Default object announcements come in two flavors: with and without message text. Those without message text are present purely to retain a structural record of the default object in the internal transcript; we can simply remove these, since the actions that created them didn't even want default messages. For those that do include message text, remove them as well, but also use their actions to replace the corresponding parent actions, so that the parent actions reflect what actually happened with the final defaulted objects.

"Unstack" a recursive group of nested announcements. Adds the recursive group to the output group vector in chronological order, and returns the index of the next item after the recursive group.

A recursive group is a set of nested implicit commands, where one implicit command triggered another, which triggered another, and so on. The innermost of the nested set is the one that's actually executed first chronologically, since an implied command must be carried out before its enclosing command can proceed. For example:

>go south
(first opening the door)
(first unlocking the door)
(first taking the key out of the bag)

Going south implies opening the door, but before we can open the door, we must unlock it, and before we can unlock it we must be holding the key. In report order, the innermost command is listed last, since it's nested within the enclosing commands. Chronologically, though, the innermost command is actually executed first. The purpose of this routine is to unstack these nested sets, rearranging them into chronological order.