RosettaCodeData/Task/Undefined-values/Common-Lisp/undefined-values-1.lisp

11 lines
402 B
Common Lisp

;; assumption: none of these variables initially exist
(defvar *x*) ;; variable exists now, but has no value
(defvar *y* 42) ;; variable exists now, and has a value
(special-variable-p '*x*) -> T ;; Symbol *x* names a special variable
(boundp '*x*) -> NIL ;; *x* has no binding
(boundp '*y*) -> T
(special-variable-p '*z*) -> NIL ;; *z* does not name a special variable