lispdoc - results for fdefinition

(fdefinition name)

Function: Return name's global function definition taking care to respect any encapsulations and to return the innermost encapsulated definition. This is SETF'able.

Example:

(defun get-late-bind-function (package name)
  "Tries to find a function that may not exist at read, compile
or load time, ie totally dynamic."
  (let* ((pack (find-package package))
         (sym
          (find-symbol (symbol-name name) pack)))
    (when (fboundp sym) (fdefinition sym))))

Mentioned in:
CLtL2 - 28.2. Functions in the Programmer Interface
CLtL2 - 7.1. Constants and Variables
CLtL2 - 7.1. Reference
HyperSpec - Accessor FDEFINITION