10.2.17 boundp [Function]

boundp symbol ⇒ generalized-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 , setq , symbol-value , makunbound

Notes::

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