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| ANSI Common Lisp 5 Data and Control Flow 5.3 Dictionary of Data and Control Flow
5.3.4 fboundp | Function
  Syntax: fboundp name generalized-boolean Pronunciation: [ 'ef'baündpê ] Arguments and Values: name - a function name. generalized-boolean - a generalized boolean. Description: Returns true if name is fbound; otherwise, returns false. Examples:
       (fboundp 'car)  true
       (fboundp 'nth-value)  false
       (fboundp 'with-open-file)  true
       (fboundp 'unwind-protect)  true
       (defun my-function (x) x)   MY-FUNCTION
       (fboundp 'my-function)  true
       (let ((saved-definition (symbol-function 'my-function)))
         (unwind-protect (progn (fmakunbound 'my-function)
                                (fboundp 'my-function))
           (setf (symbol-function 'my-function) saved-definition)))
       false
       (fboundp 'my-function)  true
       (defmacro my-macro (x) `',x)   MY-MACRO
       (fboundp 'my-macro)  true
       (fmakunbound 'my-function)   MY-FUNCTION
       (fboundp 'my-function)  false
       (flet ((my-function (x) x))
         (fboundp 'my-function))  false
  Exceptional Situations: Should signal an error of type type-error if name is not a function name. See Also: symbol-function, fmakunbound, fdefinition Notes: It is permissible to call symbol-function on any symbol that is fbound. fboundp is sometimes used to "guard" an access to the function cell, as in:
      (if (fboundp x) (symbol-function x))
Defining a setf expander F does not cause the setf function `(setf F)` to become defined. Allegro CL Implementation Details: None.

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