;;; Helper macros

(defmacro defdfun (name args doc &body body)
  `(eval-when (:compile-toplevel :load-toplevel :execute)
     (unless (fboundp ',name)
       ;; Non-executed, non-toplevel DEFUNs cause a bug in SBCL type
       ;; inference, so avoid DEFUN specifically
       #+sbcl (setf (fdefinition ',name) (lambda ,args ,@body))
       #-sbcl (defun ,name ,args ,@body))
     (setf (documentation ',name 'function)
           (or (documentation ',name 'function) ,doc))))