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The concept of
objects that float to the end of a page or chapter is
well-known in the context of typesetting. Footnotes float to
the end of the page, while figures may float to the end of a
chapter. AsTeR provides the same functionality with rendering
rules that delay audio rendering. In this section, we describe
rendering rules that enable footnotes to float (in general
instances of any object type) to the end of different
hierarchical units in the document model.
We achieve this by first implementing a mechanism for
delayed evaluation in Lisp.
[displaymath5870]
delays the execution of action action until
triggered by trigger. In a rendering rule that
floats an object, action is a function object
whose body specifies audio events to be executed. The delayed
action is triggered by executing
[displaymath5871]
This forces all actions that are waiting for
trigger in the order in which they were
delayed. The delayed evaluation provided by this
mechanism is of course more widely applicable.
TV Raman
Thu Mar 9 20:10:41 EST 1995