*top-level-read-eval-print-loop-wrapper*

The value of this variable should be nil or a function which takes two arguments and typically makes some customizations before applying the first argument to the second. The initial value of this variable is nil, which has no effect.

In this rather trivial example, we define the wrapper so that the command character (the value of *command-char*, initially #\:) is #\$. Of course, in a real example, something more complex would be done, but the form would be similar to this example.

(defun my-lisp-listener-wrapper (function args)
  (let ((tpl:*command-char* #\$))
    (apply function args)))

;; After we evaluate the following forms, the command character will be $
;; (rather than :) in any new lisp listener process.

(setq tpl:*top-level-read-eval-print-loop-wrapper*
      'my-lisp-listener-wrapper) 

This variable is not available in Lisp images built with a minimal top level, that is built with the include-tpl argument to build-lisp-image specified nil. See Minimal top levels in building-images.htm for information on minimal top levels.

See top-level.htm for more information on the top level.

Copyright (c) 1998-2002, Franz Inc. Oakland, CA., USA. All rights reserved.
Documentation for Allegro CL version 6.2. This page was not revised from the 6.1 page.
Created 2002.2.26.