Artifact c2bf6f8680e3d002eb2090f3e413d2ae237592df8dc9b51c70e95db361affa93:

• File psl-1983/3-1/nmode/rec.sl — part of check-in [eb17ceb7f6] at 2020-04-21 19:40:01 on branch master — Add Reduce 3.0 to the historical section of the archive, and some more
  files relating to version sof PSL from the early 1980s. Thanks are due to
  Paul McJones and Nelson Beebe for these, as well as to all the original
  authors.

  git-svn-id: https://svn.code.sf.net/p/reduce-algebra/code/historical@5328 2bfe0521-f11c-4a00-b80e-6202646ff360 (user: arthurcnorman@users.sourceforge.net, size: 2906) [annotate] [blame] [check-ins using] [more...]

• File psl-1983/nmode/rec.sl — part of check-in [eb17ceb7f6] at 2020-04-21 19:40:01 on branch master — Add Reduce 3.0 to the historical section of the archive, and some more
  files relating to version sof PSL from the early 1980s. Thanks are due to
  Paul McJones and Nelson Beebe for these, as well as to all the original
  authors.

  git-svn-id: https://svn.code.sf.net/p/reduce-algebra/code/historical@5328 2bfe0521-f11c-4a00-b80e-6202646ff360 (user: arthurcnorman@users.sourceforge.net, size: 2906) [annotate] [blame] [check-ins using]

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% REC.SL - Recursive Editing Functioons
%
% Author:	Jeffrey Soreff
%		Hewlett-Packard/CRC
% Date:		24 Jan 1983
%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

(compiletime (load extended-char fast-int objects))

% External variables used here:

(fluid '(recurse-mode nmode-current-buffer))

% Global variables defined here:

(fluid '(recurse-query recurse-query-answered))

% Recurse-Query will be T if the user leaves a recursive editing level
% with a "Y". It will be nil if the user leaves with an "N". In either
% of those cases recurse-query-answered will be set to T. If the user
% leaves the recursive editing level by some other means then
% recurse-query-answered will be NIL.

(de recursive-edit-y-or-n (buffer outer-message inner-message)
  % This function allows a user to make a yes or no decision about
  % some buffer, either before looking at it with the editor or while
  % editing within it. Before starting to edit the user is prompted
  % with the outer message. This function takes care of interpreting a
  % Y or N prior to editing and of providing a prompt (the outer
  % message) before editing. The call to recursive-edit takes care of
  % the prompt during editing and of interpreting a Y or N during
  % editing. This function returns a boolean value.
  (prog1
   (while t
     (write-message outer-message)
     (let ((ch (x-char-upcase (input-extended-character))))
       (when (= ch (x-char Y)) (exit T))
       (when (= ch (x-char N)) (exit NIL))
       (when (= ch (x-char C-R))
	 (recursive-edit buffer recurse-mode inner-message))
       (when recurse-query-answered (exit recurse-query))))
   (write-message "")))    

(de recursive-edit (new-buffer mode inner-message)
  % This function triggers the recursive editing loop, switching
  % buffers, setting the new buffer temporarily into a user selected
  % mode, and returning the buffer and mode to their old values after
  % the editing. This function returns a value only through global
  % variables, particularly recurse-query and recurse-query-answered.
  (let ((old-buffer nmode-current-buffer)
	(old-mode (=> new-buffer mode)))
    (=> new-buffer set-mode mode)
    (buffer-select new-buffer)
    (let ((old-message (write-message inner-message)))
      (setf recurse-query-answered NIL)
      (nmode-reader NIL)
      (write-message old-message))
    (=> new-buffer set-mode old-mode)
    (buffer-select old-buffer))) % Note: resets nmode-current-buffer
  
(de affirmative-exit ()
  % Returns T from a recursive editing mode, usually bound to Y.
  (setf recurse-query T)
  (setf recurse-query-answered T)
  (exit-nmode-reader))

(de negative-exit ()
  % Returns NIL from a recursive editing mode, usually bound to N.
  (setf recurse-query NIL)
  (setf recurse-query-answered T)
  (exit-nmode-reader))