boundp symbol → generalized-boolean

symbol — a symbol.

generalized-boolean — a generalized boolean.

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

(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

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

set, setq, symbol-value, makunbound

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