From 0ccc83d9d3e17856aa962e7748277cafcf76d921 Mon Sep 17 00:00:00 2001 From: Stefan Monnier Date: Mon, 1 May 2006 13:30:59 +0000 Subject: [PATCH] (nil and t): Add `booleanp' predicate. --- lispref/intro.texi | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/lispref/intro.texi b/lispref/intro.texi index b2294be4c2d..61dfca64b97 100644 --- a/lispref/intro.texi +++ b/lispref/intro.texi @@ -212,6 +212,11 @@ to use them as constants in a program. An attempt to change their values results in a @code{setting-constant} error. @xref{Constant Variables}. +@defun booleanp object +Return non-nil iff @var{object} is one of the two canonical boolean +values: @code{t} or @code{nil}. +@end defun + @node Evaluation Notation @subsection Evaluation Notation @cindex evaluation notation -- 2.39.5