Initial revision

1 files changed, 601 insertions, 0 deletions

diff --git a/lisp/progmodes/inf-lisp.el b/lisp/progmodes/inf-lisp.el
new file mode 100644
index 0000000000..7f78c28d97
--- /dev/null
+++ b/lisp/progmodes/inf-lisp.el
@@ -0,0 +1,601 @@
+;;; -*-Emacs-Lisp-*- cmulisp.el
+;;; Copyright Olin Shivers (1988).
+;;; Please imagine a long, tedious, legalistic 5-page gnu-style copyright
+;;; notice appearing here to the effect that you may use this code any
+;;; way you like, as long as you don't charge money for it, remove this
+;;; notice, or hold me liable for its results.
+
+;;; This replaces the standard inferior-lisp mode.
+;;; Hacked from tea.el by Olin Shivers ([email protected]). 8/88
+;;; Please send me bug reports, bug fixes, and extensions, so that I can
+;;; merge them into the master source.
+;;;
+;;; Change log at end of file.
+
+;;; This file defines a a lisp-in-a-buffer package (cmulisp mode) built on top
+;;; of comint mode.  Cmulisp mode is similar to, and intended to replace, its
+;;; counterpart in the standard gnu emacs release. This replacements is more
+;;; featureful, robust, and uniform than the released version.  The key
+;;; bindings are also more compatible with the bindings of Hemlock and Zwei
+;;; (the Lisp Machine emacs).
+
+;;; Since this mode is built on top of the general command-interpreter-in-
+;;; a-buffer mode (comint mode), it shares a common base functionality, 
+;;; and a common set of bindings, with all modes derived from comint mode.
+;;; This makes these modes easier to use.
+
+;;; For documentation on the functionality provided by comint mode, and
+;;; the hooks available for customising it, see the file comint.el.
+;;; For further information on cmulisp mode, see the comments below.
+
+;;; Needs fixin:
+;;; The load-file/compile-file default mechanism could be smarter -- it
+;;; doesn't know about the relationship between filename extensions and
+;;; whether the file is source or executable. If you compile foo.lisp
+;;; with compile-file, then the next load-file should use foo.bin for
+;;; the default, not foo.lisp. This is tricky to do right, particularly
+;;; because the extension for executable files varies so much (.o, .bin,
+;;; .lbin, .mo, .vo, .ao, ...).
+;;;
+;;; It would be nice if cmulisp (and inferior scheme, T, ...) modes
+;;; had a verbose minor mode wherein sending or compiling defuns, etc.
+;;; would be reflected in the transcript with suitable comments, e.g.
+;;; ";;; redefining fact". Several ways to do this. Which is right?
+;;;
+;;; When sending text from a source file to a subprocess, the process-mark can 
+;;; move off the window, so you can lose sight of the process interactions.
+;;; Maybe I should ensure the process mark is in the window when I send
+;;; text to the process? Switch selectable?
+
+(require 'comint)
+(provide 'cmulisp)
+
+;; YOUR .EMACS FILE
+;;=============================================================================
+;; Some suggestions for your .emacs file.
+;;
+;; ; If cmulisp lives in some non-standard directory, you must tell emacs
+;; ; where to get it. This may or may not be necessary.
+;; (setq load-path (cons (expand-file-name "~jones/lib/emacs") load-path))
+;;
+;; ; Autoload cmulisp from file cmulisp.el
+;; (autoload 'cmulisp "cmulisp"
+;;           "Run an inferior Lisp process."
+;;           t)
+;;
+;; ; Define C-c t to run my favorite command in cmulisp mode:
+;; (setq cmulisp-load-hook
+;;       '((lambda () 
+;;           (define-key cmulisp-mode-map "\C-ct" 'favorite-cmd))))
+
+
+;;; Brief Command Documentation:
+;;;============================================================================
+;;; Comint Mode Commands: (common to cmulisp and all comint-derived modes)
+;;;
+;;; m-p	    comint-previous-input    	    Cycle backwards in input history
+;;; m-n	    comint-next-input  	    	    Cycle forwards
+;;; m-c-r   comint-previous-input-matching  Search backwards in input history
+;;; return  comint-send-input
+;;; c-a     comint-bol                      Beginning of line; skip prompt.
+;;; c-d	    comint-delchar-or-maybe-eof	    Delete char unless at end of buff.
+;;; c-c c-u comint-kill-input	    	    ^u
+;;; c-c c-w backward-kill-word    	    ^w
+;;; c-c c-c comint-interrupt-subjob 	    ^c
+;;; c-c c-z comint-stop-subjob	    	    ^z
+;;; c-c c-\ comint-quit-subjob	    	    ^\
+;;; c-c c-o comint-kill-output		    Delete last batch of process output
+;;; c-c c-r comint-show-output		    Show last batch of process output
+;;;         send-invisible                  Read line w/o echo & send to proc
+;;;         comint-continue-subjob	    Useful if you accidentally suspend
+;;;					        top-level job.
+;;; comint-mode-hook is the comint mode hook.
+
+;;; CMU Lisp Mode Commands:
+;;; c-m-x   lisp-send-defun     This binding is a gnu convention.
+;;; c-c c-l lisp-load-file  	Prompt for file name; tell Lisp to load it.
+;;; c-c c-k lisp-compile-file	Prompt for file name; tell Lisp to kompile it.
+;;; 	    	    	    	Filename completion is available, of course.
+;;;
+;;; Additionally, these commands are added to the key bindings of Lisp mode:
+;;; c-m-x   lisp-eval-defun         This binding is a gnu convention.
+;;; c-c c-e lisp-eval-defun 	    Send the current defun to Lisp process.
+;;; c-x c-e lisp-eval-last-sexp     Send the previous sexp to Lisp process.
+;;; c-c m-e lisp-eval-defun-and-go  After sending the defun, switch-to-lisp.
+;;; c-c c-r lisp-eval-region        Send the current region to Lisp process.
+;;; c-c m-r lisp-eval-region-and-go After sending the region, switch-to-lisp.
+;;; c-c c-c lisp-compile-defun      Compile the current defun in Lisp process.
+;;; c-c m-c lisp-compile-defun-and-go After compiling defun, switch-to-lisp.
+;;; c-c c-z switch-to-lisp          Switch to the Lisp process buffer.
+;;; c-c c-l lisp-load-file          (See above. In a Lisp file buffer, default
+;;; c-c c-k lisp-compile-file        is to load/compile the current file.)
+;;; c-c c-d lisp-describe-sym	    Query Lisp for a symbol's description.
+;;; c-c c-a lisp-show-arglist	    Query Lisp for function's arglist.
+;;; c-c c-f lisp-show-function-documentation Query Lisp for a function's doc.
+;;; c-c c-v lisp-show-variable-documentation Query Lisp for a variable's doc.
+
+;;; cmulisp	    	    	    Fires up the Lisp process.
+;;; lisp-compile-region     	    Compile all forms in the current region.
+;;; lisp-compile-region-and-go      After compiling region, switch-to-lisp.
+;;;
+;;; CMU Lisp Mode Variables:
+;;; cmulisp-filter-regexp	    Match this => don't get saved on input hist
+;;; inferior-lisp-program   	    Name of Lisp program run-lisp executes
+;;; inferior-lisp-load-command	    Customises lisp-load-file
+;;; cmulisp-mode-hook  	    
+;;; inferior-lisp-prompt	    Initialises comint-prompt-regexp.
+;;;				    Backwards compatibility.
+;;; lisp-source-modes               Anything loaded into a buffer that's in
+;;;                                 one of these modes is considered Lisp 
+;;;                                 source by lisp-load/compile-file.
+
+;;; Read the rest of this file for more information.
+
+(defvar cmulisp-filter-regexp "\\`\\s *\\(:\\(\\w\\|\\s_\\)\\)?\\s *\\'"
+  "*What not to save on inferior Lisp's input history
+Input matching this regexp is not saved on the input history in cmulisp
+mode. Default is whitespace followed by 0 or 1 single-letter :keyword 
+(as in :a, :c, etc.)")
+
+(defvar cmulisp-mode-map nil)
+(cond ((not cmulisp-mode-map)
+       (setq cmulisp-mode-map
+	     (full-copy-sparse-keymap comint-mode-map))
+       (lisp-mode-commands cmulisp-mode-map)
+       (define-key cmulisp-mode-map "\C-x\C-e" 'lisp-eval-last-sexp)
+       (define-key cmulisp-mode-map "\C-c\C-l" 'lisp-load-file)
+       (define-key cmulisp-mode-map "\C-c\C-k" 'lisp-compile-file)
+       (define-key cmulisp-mode-map "\C-c\C-a" 'lisp-show-arglist)
+       (define-key cmulisp-mode-map "\C-c\C-d" 'lisp-describe-sym)
+       (define-key cmulisp-mode-map "\C-c\C-f" 'lisp-show-function-documentation)
+       (define-key cmulisp-mode-map "\C-c\C-v" 'lisp-show-variable-documentation)))
+
+;;; These commands augment Lisp mode, so you can process Lisp code in
+;;; the source files.
+(define-key lisp-mode-map "\M-\C-x"  'lisp-eval-defun)     ; Gnu convention
+(define-key lisp-mode-map "\C-x\C-e" 'lisp-eval-last-sexp) ; Gnu convention
+(define-key lisp-mode-map "\C-c\C-e" 'lisp-eval-defun)
+(define-key lisp-mode-map "\C-c\M-e" 'lisp-eval-defun-and-go)
+(define-key lisp-mode-map "\C-c\C-r" 'lisp-eval-region)
+(define-key lisp-mode-map "\C-c\M-r" 'lisp-eval-region-and-go)
+(define-key lisp-mode-map "\C-c\C-c" 'lisp-compile-defun)
+(define-key lisp-mode-map "\C-c\M-c" 'lisp-compile-defun-and-go)
+(define-key lisp-mode-map "\C-c\C-z" 'switch-to-lisp)
+(define-key lisp-mode-map "\C-c\C-l" 'lisp-load-file)
+(define-key lisp-mode-map "\C-c\C-k" 'lisp-compile-file)  ; "kompile" file
+(define-key lisp-mode-map "\C-c\C-a" 'lisp-show-arglist)
+(define-key lisp-mode-map "\C-c\C-d" 'lisp-describe-sym)
+(define-key lisp-mode-map "\C-c\C-f" 'lisp-show-function-documentation)
+(define-key lisp-mode-map "\C-c\C-v" 'lisp-show-variable-documentation)
+
+
+(defvar inferior-lisp-program "lisp"
+  "*Program name for invoking an inferior Lisp with `cmulisp'.")
+
+(defvar inferior-lisp-load-command "(load \"%s\")\n"
+  "*Format-string for building a Lisp expression to load a file.
+This format string should use %s to substitute a file name
+and should result in a Lisp expression that will command the inferior Lisp
+to load that file.  The default works acceptably on most Lisps.
+The string \"(progn (load \\\"%s\\\" :verbose nil :print t) (values))\\\n\"
+produces cosmetically superior output for this application,
+but it works only in Common Lisp.")
+
+(defvar inferior-lisp-prompt "^[^> ]*>+:? *"
+  "Regexp to recognise prompts in the inferior Lisp.
+Defaults to \"^[^> ]*>+:? *\", which works pretty good for Lucid, kcl,
+and franz. This variable is used to initialise comint-prompt-regexp in the 
+cmulisp buffer.
+
+More precise choices:
+Lucid Common Lisp: \"^\\(>\\|\\(->\\)+\\) *\"
+franz: \"^\\(->\\|<[0-9]*>:\\) *\"
+kcl: \"^>+ *\"
+
+This is a fine thing to set in your .emacs file.")
+
+(defvar cmulisp-mode-hook '()
+  "*Hook for customising cmulisp mode")
+
+(defun cmulisp-mode () 
+  "Major mode for interacting with an inferior Lisp process.  
+Runs a Lisp interpreter as a subprocess of Emacs, with Lisp I/O through an
+Emacs buffer.  Variable inferior-lisp-program controls which Lisp interpreter
+is run.  Variables inferior-lisp-prompt, cmulisp-filter-regexp and
+inferior-lisp-load-command can customize this mode for different Lisp
+interpreters.
+
+For information on running multiple processes in multiple buffers, see
+documentation for variable cmulisp-buffer.
+
+\\{cmulisp-mode-map}
+
+Customisation: Entry to this mode runs the hooks on comint-mode-hook and
+cmulisp-mode-hook (in that order).
+
+You can send text to the inferior Lisp process from other buffers containing
+Lisp source.  
+    switch-to-lisp switches the current buffer to the Lisp process buffer.
+    lisp-eval-defun sends the current defun to the Lisp process.
+    lisp-compile-defun compiles the current defun.
+    lisp-eval-region sends the current region to the Lisp process.
+    lisp-compile-region compiles the current region.
+
+    lisp-eval-defun-and-go, lisp-compile-defun-and-go,
+        lisp-eval-region-and-go, and lisp-compile-region-and-go
+        switch to the Lisp process buffer after sending their text.
+
+Commands:
+Return after the end of the process' output sends the text from the 
+    end of process to point.
+Return before the end of the process' output copies the sexp ending at point
+    to the end of the process' output, and sends it.
+Delete converts tabs to spaces as it moves back.
+Tab indents for Lisp; with argument, shifts rest
+    of expression rigidly with the current line.
+C-M-q does Tab on each line starting within following expression.
+Paragraphs are separated only by blank lines.  Semicolons start comments.
+If you accidentally suspend your process, use \\[comint-continue-subjob]
+to continue it."
+  (interactive)
+  (comint-mode)
+  (setq comint-prompt-regexp inferior-lisp-prompt)
+  (setq major-mode 'cmulisp-mode)
+  (setq mode-name "CMU Lisp")
+  (setq mode-line-process '(": %s"))
+  (if (string-match "^18.4" emacs-version) ; hack.
+      (lisp-mode-variables)    ; This is right for 18.49  
+      (lisp-mode-variables t)) ; This is right for 18.50
+  (use-local-map cmulisp-mode-map)    ;c-c c-k for "kompile" file
+  (setq comint-get-old-input (function lisp-get-old-input))
+  (setq comint-input-filter (function lisp-input-filter))
+  (setq comint-input-sentinel 'ignore)
+  (run-hooks 'cmulisp-mode-hook))
+
+(defun lisp-get-old-input ()
+  "Snarf the sexp ending at point"
+  (save-excursion
+    (let ((end (point)))
+      (backward-sexp)
+      (buffer-substring (point) end))))
+
+(defun lisp-input-filter (str)
+  "Don't save anything matching cmulisp-filter-regexp"
+  (not (string-match cmulisp-filter-regexp str)))
+
+(defun cmulisp ()
+  "Run an inferior Lisp process, input and output via buffer *cmulisp*.
+If there is a process already running in *cmulisp*, just switch to that buffer.
+Takes the program name from the variable inferior-lisp-program.
+\(Type \\[describe-mode] in the process buffer for a list of commands.)"
+  (interactive)
+  (cond ((not (comint-check-proc "*cmulisp*"))
+	 (set-buffer (make-comint "cmulisp" inferior-lisp-program))
+	 (cmulisp-mode)))
+  (setq cmulisp-buffer "*cmulisp*")
+  (switch-to-buffer "*cmulisp*"))
+
+(defun lisp-eval-region (start end)
+  "Send the current region to the inferior Lisp process."
+  (interactive "r")
+  (comint-send-region (cmulisp-proc) start end)
+  (comint-send-string (cmulisp-proc) "\n"))
+
+(defun lisp-eval-defun ()
+  "Send the current defun to the inferior Lisp process."
+  (interactive)
+  (save-excursion
+   (end-of-defun)
+   (let ((end (point)))
+     (beginning-of-defun)
+     (lisp-eval-region (point) end))))
+
+(defun lisp-eval-last-sexp ()
+  "Send the previous sexp to the inferior Lisp process."
+  (interactive)
+  (lisp-eval-region (save-excursion (backward-sexp) (point)) (point)))
+
+;;; CommonLisp COMPILE sux. 
+(defun lisp-compile-region (start end)
+  "Compile the current region in the inferior Lisp process."
+  (interactive "r")
+  (comint-send-string (cmulisp-proc)
+    (format "(funcall (compile nil `(lambda () (progn 'compile %s))))\n"
+	    (buffer-substring start end))))
+			 
+(defun lisp-compile-defun ()
+  "Compile the current defun in the inferior Lisp process."
+  (interactive)
+  (save-excursion
+    (end-of-defun)
+    (let ((e (point)))
+      (beginning-of-defun)
+      (lisp-compile-region (point) e))))
+
+(defun switch-to-lisp (eob-p)
+  "Switch to the inferior Lisp process buffer.
+With argument, positions cursor at end of buffer."
+  (interactive "P")
+  (if (get-buffer cmulisp-buffer)
+      (pop-to-buffer cmulisp-buffer)
+      (error "No current process buffer. See variable cmulisp-buffer."))
+  (cond (eob-p
+	 (push-mark)
+	 (goto-char (point-max)))))
+
+(defun lisp-eval-region-and-go (start end)
+  "Send the current region to the inferior Lisp, 
+and switch to the process buffer."
+  (interactive "r")
+  (lisp-eval-region start end)
+  (switch-to-lisp t))
+
+(defun lisp-eval-defun-and-go ()
+  "Send the current defun to the inferior Lisp, 
+and switch to the process buffer."
+  (interactive)
+  (lisp-eval-defun)
+  (switch-to-lisp t))
+
+(defun lisp-compile-region-and-go (start end)
+  "Compile the current region in the inferior Lisp, 
+and switch to the process buffer."
+  (interactive "r")
+  (lisp-compile-region start end)
+  (switch-to-lisp t))
+
+(defun lisp-compile-defun-and-go ()
+  "Compile the current defun in the inferior Lisp, 
+and switch to the process buffer."
+  (interactive)
+  (lisp-compile-defun)
+  (switch-to-lisp t))
+
+;;; A version of the form in H. Shevis' soar-mode.el package. Less robust.
+;(defun lisp-compile-sexp (start end)
+;  "Compile the s-expression bounded by START and END in the inferior lisp.
+;If the sexp isn't a DEFUN form, it is evaluated instead."
+;    (cond ((looking-at "(defun\\s +")
+;	   (goto-char (match-end 0))
+;	   (let ((name-start (point)))
+;	     (forward-sexp 1)
+;	     (process-send-string "cmulisp" (format "(compile '%s #'(lambda "
+;						 (buffer-substring name-start
+;								   (point)))))
+;	   (let ((body-start (point)))
+;	     (goto-char start) (forward-sexp 1) ; Can't use end-of-defun.
+;	     (process-send-region "cmulisp" (buffer-substring body-start (point))))
+;	   (process-send-string "cmulisp" ")\n"))
+;	  (t (lisp-eval-region start end)))))
+;
+;(defun lisp-compile-region (start end)
+;  "Each s-expression in the current region is compiled (if a DEFUN)
+;or evaluated (if not) in the inferior lisp."
+;  (interactive "r")
+;  (save-excursion
+;    (goto-char start) (end-of-defun) (beginning-of-defun) ; error check
+;    (if (< (point) start) (error "region begins in middle of defun"))
+;    (goto-char start)
+;    (let ((s start))
+;      (end-of-defun)
+;      (while (<= (point) end) ; Zip through
+;	(lisp-compile-sexp s (point)) ; compiling up defun-sized chunks.
+;	(setq s (point))
+;	(end-of-defun))
+;      (if (< s end) (lisp-compile-sexp s end)))))
+;;;
+;;; End of HS-style code
+
+
+(defvar lisp-prev-l/c-dir/file nil
+  "Saves the (directory . file) pair used in the last lisp-load-file or
+lisp-compile-file command. Used for determining the default in the 
+next one.")
+
+(defvar lisp-source-modes '(lisp-mode)
+  "*Used to determine if a buffer contains Lisp source code.
+If it's loaded into a buffer that is in one of these major modes, it's
+considered a Lisp source file by lisp-load-file and lisp-compile-file.
+Used by these commands to determine defaults.")
+
+(defun lisp-load-file (file-name)
+  "Load a Lisp file into the inferior Lisp process."
+  (interactive (comint-get-source "Load Lisp file: " lisp-prev-l/c-dir/file
+				  lisp-source-modes nil)) ; NIL because LOAD
+                                                   ; doesn't need an exact name
+  (comint-check-source file-name) ; Check to see if buffer needs saved.
+  (setq lisp-prev-l/c-dir/file (cons (file-name-directory    file-name)
+				     (file-name-nondirectory file-name)))
+  (comint-send-string (cmulisp-proc)
+		      (format inferior-lisp-load-command file-name)))
+
+
+(defun lisp-compile-file (file-name)
+  "Compile a Lisp file in the inferior Lisp process."
+  (interactive (comint-get-source "Compile Lisp file: " lisp-prev-l/c-dir/file
+				  lisp-source-modes nil)) ; NIL = don't need
+                                                          ; suffix .lisp
+  (comint-check-source file-name) ; Check to see if buffer needs saved.
+  (setq lisp-prev-l/c-dir/file (cons (file-name-directory    file-name)
+				     (file-name-nondirectory file-name)))
+  (comint-send-string (cmulisp-proc) (concat "(compile-file \""
+					     file-name
+					     "\"\)\n")))
+
+
+
+;;; Documentation functions: function doc, var doc, arglist, and
+;;; describe symbol.
+;;; ===========================================================================
+
+;;; Command strings
+;;; ===============
+
+(defvar lisp-function-doc-command
+  "(let ((fn '%s))
+     (format t \"Documentation for ~a:~&~a\"
+	     fn (documentation fn 'function))
+     (values))\n"
+  "Command to query inferior Lisp for a function's documentation.")
+
+(defvar lisp-var-doc-command
+  "(let ((v '%s))
+     (format t \"Documentation for ~a:~&~a\"
+	     v (documentation v 'variable))
+     (values))\n"
+  "Command to query inferior Lisp for a variable's documentation.")
+
+(defvar lisp-arglist-command
+  "(let ((fn '%s))
+     (format t \"Arglist for ~a: ~a\" fn (arglist fn))
+     (values))\n"
+  "Command to query inferior Lisp for a function's arglist.")
+
+(defvar lisp-describe-sym-command
+  "(describe '%s)\n"
+  "Command to query inferior Lisp for a variable's documentation.")
+
+
+;;; Ancillary functions
+;;; ===================
+
+;;; Reads a string from the user.
+(defun lisp-symprompt (prompt default)
+  (list (let* ((prompt (if default
+			   (format "%s (default %s): " prompt default)
+			   (concat prompt ": ")))
+	       (ans (read-string prompt)))
+	  (if (zerop (length ans)) default ans))))
+
+
+;;; Adapted from function-called-at-point in help.el.
+(defun lisp-fn-called-at-pt ()
+  "Returns the name of the function called in the current call.
+Nil if it can't find one."
+  (condition-case nil
+      (save-excursion
+	(save-restriction
+	  (narrow-to-region (max (point-min) (- (point) 1000)) (point-max))
+	  (backward-up-list 1)
+	  (forward-char 1)
+	  (let ((obj (read (current-buffer))))
+	    (and (symbolp obj) obj))))
+    (error nil)))
+
+
+;;; Adapted from variable-at-point in help.el.
+(defun lisp-var-at-pt ()
+  (condition-case ()
+      (save-excursion
+	(forward-sexp -1)
+	(skip-chars-forward "'")
+	(let ((obj (read (current-buffer))))
+	  (and (symbolp obj) obj)))
+    (error nil)))
+
+
+;;; Documentation functions: fn and var doc, arglist, and symbol describe.
+;;; ======================================================================
+
+(defun lisp-show-function-documentation (fn)
+  "Send a command to the inferior Lisp to give documentation for function FN.
+See variable lisp-function-doc-command."
+  (interactive (lisp-symprompt "Function doc" (lisp-fn-called-at-pt)))
+  (comint-proc-query (cmulisp-proc) (format lisp-function-doc-command fn)))
+
+(defun lisp-show-variable-documentation (var)
+  "Send a command to the inferior Lisp to give documentation for function FN.
+See variable lisp-var-doc-command."
+  (interactive (lisp-symprompt "Variable doc" (lisp-var-at-pt)))
+  (comint-proc-query (cmulisp-proc) (format lisp-var-doc-command var)))
+
+(defun lisp-show-arglist (fn)
+  "Sends an query to the inferior Lisp for the arglist for function FN.
+See variable lisp-arglist-command."
+  (interactive (lisp-symprompt "Arglist" (lisp-fn-called-at-pt)))
+  (comint-proc-query (cmulisp-proc) (format lisp-arglist-command fn)))
+
+(defun lisp-describe-sym (sym)
+  "Send a command to the inferior Lisp to describe symbol SYM.
+See variable lisp-describe-sym-command."
+  (interactive (lisp-symprompt "Describe" (lisp-var-at-pt)))
+  (comint-proc-query (cmulisp-proc) (format lisp-describe-sym-command sym)))
+
+
+(defvar cmulisp-buffer nil "*The current cmulisp process buffer.
+
+MULTIPLE PROCESS SUPPORT
+===========================================================================
+Cmulisp.el supports, in a fairly simple fashion, running multiple Lisp
+processes. To run multiple Lisp processes, you start the first up with
+\\[cmulisp]. It will be in a buffer named *cmulisp*. Rename this buffer
+with \\[rename-buffer]. You may now start up a new process with another
+\\[cmulisp]. It will be in a new buffer, named *cmulisp*. You can
+switch between the different process buffers with \\[switch-to-buffer].
+
+Commands that send text from source buffers to Lisp processes --
+like lisp-eval-defun or lisp-show-arglist -- have to choose a process
+to send to, when you have more than one Lisp process around. This
+is determined by the global variable cmulisp-buffer. Suppose you
+have three inferior lisps running:
+    Buffer	Process
+    foo		cmulisp
+    bar		cmulisp<2>
+    *cmulisp*   cmulisp<3>
+If you do a \\[lisp-eval-defun-and-go] command on some Lisp source code, 
+what process do you send it to?
+
+- If you're in a process buffer (foo, bar, or *cmulisp*), 
+  you send it to that process.
+- If you're in some other buffer (e.g., a source file), you
+  send it to the process attached to buffer cmulisp-buffer.
+This process selection is performed by function cmulisp-proc.
+
+Whenever \\[cmulisp] fires up a new process, it resets cmulisp-buffer
+to be the new process's buffer. If you only run one process, this will
+do the right thing. If you run multiple processes, you can change
+cmulisp-buffer to another process buffer with \\[set-variable].
+
+More sophisticated approaches are, of course, possible. If you find youself
+needing to switch back and forth between multiple processes frequently,
+you may wish to consider ilisp.el, a larger, more sophisticated package
+for running inferior Lisp processes. The approach taken here is for a
+minimal, simple implementation. Feel free to extend it.")
+
+(defun cmulisp-proc ()
+  "Returns the current cmulisp process. See variable cmulisp-buffer."
+  (let ((proc (get-buffer-process (if (eq major-mode 'inferior-lisp-mode)
+				      (current-buffer)
+				      cmulisp-buffer))))
+    (or proc
+	(error "No current process. See variable cmulisp-buffer"))))
+
+
+;;; Do the user's customisation...
+;;;===============================
+(defvar cmulisp-load-hook nil
+  "This hook is run when cmulisp is loaded in.
+This is a good place to put keybindings.")
+	
+(run-hooks 'cmulisp-load-hook)
+
+;;; CHANGE LOG
+;;; ===========================================================================
+;;; 5/24/90 Olin
+;;; - Split cmulisp and cmushell modes into separate files. 
+;;;   Not only is this a good idea, it's apparently the way it'll be rel 19.
+;;; - Upgraded process sends to use comint-send-string instead of
+;;;   process-send-string.
+;;; - Explicit references to process "cmulisp" have been replaced with
+;;;   (cmulisp-proc). This allows better handling of multiple process bufs.
+;;; - Added process query and var/function/symbol documentation
+;;;   commands. Based on code written by Douglas Roberts.
+;;; - Added lisp-eval-last-sexp, bound to C-x C-e.
+;;;
+;;; 9/20/90 Olin
+;;; Added a save-restriction to lisp-fn-called-at-pt. This bug and fix
+;;; reported by Lennart Staflin.
+;;;
+;;; 3/12/90 Olin
+;;; - lisp-load-file and lisp-compile-file no longer switch-to-lisp.
+;;;   Tale suggested this.