Example of let binding a special

(defvar *default-file*) ; no value

(defvar *default-directory "c:/")

(defun process-file (file directory)

(let ((*default-file* file)

(*default-directory* directory))

(print *default-file*)

(print *default-directory*)

(loader)))

(defun loader ()

;; This will signal an error unless called

;; by process-file

(load (merge-pathnames *default-file*

*default-directory*)))

When process-file completes, *default-file* and *default-directory* revert to previous settings.

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