Floating objects

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.

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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

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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