boundp (ANSI and GNU Common Lisp Document)

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#### 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.