10.2.17 boundp [Function]

boundp symbolgeneralized-boolean

Arguments and Values::

symbol—a symbol.

generalized-boolean—a generalized boolean.

Description::

Returns true if symbol is bound; otherwise, returns false.

Examples::

 (setq x 1) ⇒  1
 (boundp 'x) ⇒  true
 (makunbound 'x) ⇒  X
 (boundp 'x) ⇒  false
 (let ((x 2)) (boundp 'x)) ⇒  false
 (let ((x 2)) (declare (special x)) (boundp 'x)) ⇒  true

Exceptional Situations::

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

See Also::

set [Function] , setq [Special Form] , symbol-value [Accessor] , makunbound [Function]

Notes::

The function bound determines only whether a symbol has a value in the global environment; any lexical bindings are ignored.