interactive-stream-p

ToC

Allegro CL

ANSI Common Lisp

21 Streams

21.2 Dictionary of Streams

21.2.10 interactive-stream-p

Function

Syntax:

interactive-stream-p stream

generalized-boolean

Arguments and Values:

stream - a stream.

generalized-boolean - a generalized boolean.

Description:

Returns true if stream is an interactive stream; otherwise, returns false.

Examples:

 (when (> measured limit)
   (let ((error (round (* (- measured limit) 100)
                       limit)))
     (unless (if (interactive-stream-p *query-io*)
                 (yes-or-no-p "The frammis is out of tolerance by ~D%.~@
                               Is it safe to proceed? " error)
                 (< error 15))  ;15% is acceptable
       (error "The frammis is out of tolerance by ~D%." error))))

Exceptional Situations:

Should signal an error of type type-error if stream is not a stream.

See Also:

Section 21.1 Stream Concepts

Allegro CL Implementation Details:

See Extensions to cl:interactive-stream-p in implementation.htm for information on the Allegro CL implementation. Note the links are to the documentation for the current Allegro CL version. Replace /current/ in the URL with the Allegro CL version number to see similar documentation is earlier releases.