![[LISPWORKS]](../Graphics/LWSmall.gif)
Syntax:
clear-input &optional input-stream => nil
Arguments and Values:
input-stream---an input stream designator. The default is standard input.
Description:
Clears any available input from input-stream.
If clear-input does not make sense for input-stream, then clear-input does nothing.
Examples:
;; The exact I/O behavior of this example might vary from implementation
;; to implementation depending on the kind of interactive buffering that
;; occurs. (The call to SLEEP here is intended to help even out the
;; differences in implementations which do not do line-at-a-time buffering.)
(defun read-sleepily (&optional (clear-p nil) (zzz 0))
(list (progn (print '>) (read))
;; Note that input typed within the first ZZZ seconds
;; will be discarded.
(progn (print '>)
(if zzz (sleep zzz))
(print '>>)
(if clear-p (clear-input))
(read))))
(read-sleepily)
>> > 10
>> >
>> >> 20
=> (10 20)
(read-sleepily t)
>> > 10
>> >
>> >> 20
=> (10 20)
(read-sleepily t 10)
>> > 10
>> > 20 ; Some implementations won't echo typeahead here.
>> >> 30
=> (10 30)
Side Effects:
The input-stream is modified.
Affected By:
Exceptional Situations:
Should signal an error of type type-error if input-stream is not a stream designator.
See Also:
Notes: None.