Buy the book!
|[ < ]||[ > ]||[ << ]||[ Up ]||[ >> ]||[Top]||[Contents]||[Index]||[ ? ]|
A bool-vector is much like a vector, except that it stores only the
nil. If you try to store any non-
value into an element of the bool-vector, the effect is to store
t there. As with all arrays, bool-vector indices start from 0,
and the length cannot be changed once the bool-vector is created.
Bool-vectors are constants when evaluated.
There are two special functions for working with bool-vectors; aside from that, you manipulate them with same functions used for other kinds of arrays.
tif object is a bool-vector, and
Here is an example of creating, examining, and updating a bool-vector. Note that the printed form represents up to 8 boolean values as a single character.
(setq bv (make-bool-vector 5 t)) => #&5"^_" (aref bv 1) => t (aset bv 3 nil) => nil bv => #&5"^W"
These results make sense because the binary codes for control-_ and control-W are 11111 and 10111, respectively.
|webmaster donations bookstore||delorie software privacy|
|Copyright © 2003 by The Free Software Foundation||Updated Jun 2003|