Page 187	Table of Contents	Index	Page 189
	Chapters
	1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 A, B, C, D, E

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CHAPTER 21. INCREMENTAL REDISPLAY

21.4 Incremental Redisplay Stream Protocol

=> stream-redisplayable-p stream [Generic Function]
Returns true for any stream that maintains an output history and supports the incremental
redisplay protocol, otherwise returns false.

=> stream-redisplaying-p stream [Generic Function]
Returns true if the stream is currently doing redisplay (that is, is inside of a call to redisplay),
otherwise returns false.

=> incremental-redisplay stream position erases moves draws erase-overlapping move-overlapping
[Generic Function]
Performs the incremental update on stream according to the difference set comprised by erases,
moves, draws, erase-overlapping, and move-overlapping, which are values returned by compute-
difference-set. position is a point object that represents the start position of the topmost
output record that will be redisplayed.
incremental-redisplay can be called on any extended output stream.

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Page 187	Table of Contents	Index	Page 189
	Chapters
	1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 A, B, C, D, E