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Function FUNCTIONP

Syntax

  • functionp objectgeneralized-boolean

Arguments and Values

Description

Returns true if object is of type function; otherwise, returns false.

Examples

(functionp 'append)

false

(functionp #'append)

true

(functionp (symbol-function 'append))

true

(flet ((f () 1)) (functionp #'f))

true

(functionp (compile nil '(lambda () 259)))

true

(functionp nil)

false

(functionp 12)

false

(functionp '(lambda (x) (* x x)))

false

(functionp #'(lambda (x) (* x x)))

true

Side Effects

None.

Affected By

None.

Exceptional Situations

None.

See Also

None.

Notes

(functionp object) ≡ (typep object 'function)

\issue{FUNCTION-TYPE:X3J13-MARCH-88}