Function: booleanp

booleanp is a byte-compiled function defined in subr.el.gz.

Signature

(booleanp OBJECT)

Documentation

Return t if OBJECT is one of the two canonical boolean values: t or nil.

Otherwise, return nil.

View in manual

Probably introduced at or before Emacs version 22.1.

Source Code

;; Defined in /usr/src/emacs/lisp/subr.el.gz
(defun booleanp (object)
  "Return t if OBJECT is one of the two canonical boolean values: t or nil.
Otherwise, return nil."
  (declare (pure t) (side-effect-free error-free))
  (and (memq object '(nil t)) t))