fboundp

Type:	-	predicate function (subr)
Source:	-	xlbfun.c

Syntax

(fboundp symbol)

symbol - the symbol expression to check for a value
returns -  T  if a functional value is bound to the symbol, NIL otherwise

Description

The 'fboundp' predicate function checks to see if 'symbol' is a symbol with a function definition bound to it.  T  is returned if 'symbol' has a function value, NIL is returned otherwise. Note that 'symbol' is a symbol expression, it is evaluated and the resulting expression is the one that is checked.

Examples

(defun foo (x) (print x))       ; set up function FOO
(fboundp 'foo)                  ; returns T - FOO is closure
(fboundp 'car)                  ; returns T - CAR is subr

(setq myvar 'goo)               ; set up MYVAR to have value GOO
(fboundp myvar)                 ; returns NIL - because GOO has no value yet
(defmacro goo () (print "hi"))  ; define GOO macro
(fboundp myvar)                 ; returns T

(fboundp 'a)                    ; returns NIL
(fboundp '1)                    ; error: bad argument type - 1
(fboundp "hi")                  ; error: bad argument type - "hi"

See the fboundp predicate function in the XLISP 2.0 manual.

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