Artifact 2915716e42b995e8a1c9659107ef28b3087f6f49d3e8b24cf8ec1bd44eae3ba3:

• File psl-1983/emode/prompting.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: 7008) [annotate] [blame] [check-ins using] [more...]

%
% PROMPTING.SL - "Prompting" utilities for EMODE.
% 
% Author:      William F. Galway
%              Symbolic Computation Group
%              Computer Science Dept.
%              University of Utah
% Date:        15 July 1982
% Copyright (c) 1982 University of Utah
%

% This file provides functions for prompting the user for information, and
% for general maintenance of the "MODE", "PROMPT", and "MESSAGE" windows.

%%%%% Changes: %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

% AS 7/16/82
% - Delay prompting for single character input.

(FLUID
  '(previous_window         % This needs to be rethought!
    prompt-immediately      % T => prompt_for_character always prompts
    prompt-was-output       % T => prompt_for_character prompted last time
    ))

(setq prompt-immediately NIL)
(setq prompt-was-output NIL)

(de prompt_for_character (prompt_string)

  % Prompt for (and echo) a single character.  Avoid prompting if the user has
  % already typed a character or types a character right away.  The fluid
  % variables PROMPT-IMMEDIATELY and PROMPT-WAS-OUTPUT are used to implement
  % sequences of prompts, as done by C-U (for example).  Within a sequence of
  % related prompts, once a prompt is output, further prompting should be done
  % immediately.

  % Echo handling needs to do better job of handling control characters, etc.

  % First check whether a character is typed quickly.  If it is, then
  % return it directly without echoing anything.
    
  (if (not prompt-immediately) (sleep-until-timeout-or-input 30))
  (setq prompt-was-output (or prompt-immediately (= (CharsInInputBuffer) 0)))
  (if (not prompt-was-output)
      (GetNextCommandCharacter)
      % else
      (show_prompt prompt_string)          % Setup & select the prompt window.
      (let ((ch (GetNextCommandCharacter)))
        (cond
          ((MetaP ch)
           (insert_string "M-")
           (InsertCharacter (UnMeta ch)))
          (T
           (InsertCharacter ch)))
        (SelectWindow previous_window)       % Go back to old window.
        ch
        )))

% Prompt for a string (terminated by newline).  Use default_string if an
% empty string is returned, (and if default_string is non-NIL).
(de prompt_for_string (prompt_string  default_string)
  (prog (return_string old-msg-string)
    % Show the default, if non-NIL.
    (cond
      (default_string
        (setf old-msg-string 
          (show_message (concat "Default is: " default_string)))))

    % Show the prompt string, and select the "prompt window" (and buffer).
    (show_prompt prompt_string)
    % Set up mode to pick up a single line of text.
    (setf ModeEstablishExpressions '((setup_insert_single_line_mode)))

    (EstablishCurrentMode)

    % Edit the buffer until an "exit" character is typed.
    (EMODEdispatchLoop)
    % Pick up the string that was typed. 
    (setf return_string (GetBufferText CurrentLineIndex))

    % Switch back to old window, etc.
    (SelectWindow previous_window)
    % Restore original "message window label", if it was "hammered".
    % Important to do this AFTER (SelectWindow previous_window)
    (cond
      (default_string (show_message old-msg-string)))

    (EstablishCurrentMode)

    % If an empty string, use default (unless it's NIL).
    (cond
      ((and
         default_string
         (equal return_string ""))
        (setf return_string default_string)))

    (return return_string)))



% Define a mode for editing a single line of text.  Nearly identical to text
% mode.  (No 100% guarantee that a single line is all that will be put into
% the buffer, since it's possible to yank back text from the kill buffer,
% for example.)
(de setup_insert_single_line_mode ()
  (progn
    (for (from i 0 31 1)
      (do
        (setf (indx MainDispatch i) 'leave_dispatch_loop)))

    (for (from i 127 255 1)
      (do
        (setf (indx MainDispatch i) 'leave_dispatch_loop)))

    % "Normal characters" insert themselves.
    (for (from i 32 126 1)
      (do
        (MakeSelfInserting i)))

    (MakeSelfInserting (char TAB))

    % It would be nice to add some of these folks who are stolen from
    % BasicDispatchSetup.  BUT, they screw up because they invoke
    % prompt_for_character (or some such), which typically will try to grab
    % the same window that this mode is invoked in causing bad confusion.
    % We need a better method (or philosphy) for doing this.

%    (SetKey (char ESC) 'EscapeAsMeta)
%    (SetKey (char (cntrl Z)) 'DoControlMeta)

    % Make right paren "bounce" to matching left paren.
    (SetKey (char '!) ) 'insert_matching_paren)

    % Other reasonable (??) commands for editing within the line.  Includes
    % most of the features of text mode.
    (SetKey (char (cntrl '!@)) 'SetMark)
    (SetKey (char (cntrl A)) '!$BeginningOfLine)
    (SetKey (char (cntrl B)) '!$BackwardCharacter)
    (SetKey (char (cntrl D)) '!$DeleteForwardCharacter)
    (SetKey (char (cntrl E)) '!$EndOfLine)
    (SetKey (char (cntrl F)) '!$ForwardCharacter)
    (SetKey (char DELETE) '!$DeleteBackwardCharacter)
    (SetKey (char (cntrl K)) 'kill_line)
    (SetKey (char (cntrl T)) 'transpose_characters)
    (SetKey (char (cntrl Y)) 'insert_kill_buffer)
    (SetKey (char (meta (cntrl B))) 'backward_sexpr)
    (SetKey (char (meta (cntrl F))) 'forward_sexpr)
    (SetKey (char (meta (cntrl K))) 'kill_forward_sexpr)
    (SetKey (char (meta (cntrl RUBOUT))) 'kill_backward_sexpr)
    (SetKey (char (meta B)) 'backward_word)
    (SetKey (char (meta D)) 'kill_forward_word)
    (SetKey (char (meta F)) 'forward_word)
    (SetKey (char (meta W)) 'copy_region)
    (SetKey (char (meta Y)) 'unkill_previous)
    (SetKey (char (meta DELETE)) 'kill_backward_word)
    (SetKey (CharSequence (cntrl X) (cntrl X))  'ExchangePointAndMark)))

% Setup and select the prompt window, "remember" the old window in Fluid
% "previous_window".
(de show_prompt (prompt_string)
  (string_in_window  prompt_string  prompt_window))

% Display a string in the "message" window, return the previous label
% string for that window.
(de show_message (strng)
  (prog (old-label)
    (setf old-label
      (string_in_window  strng  message_window))

    % Don't stay in message window.
    (SelectWindow previous_window)
    % Refresh in order to update the cursor position
    (optional_refresh)
    (return old-label)))

% "Pop up" and select a window (typically one-line and unframed).  Use
% "strng" to label the window, clear out the associated buffer, return the
% old label string.  "Remember" the previous window in fluid previous_window.
(de string_in_window (strng  window)
  (prog (old-label)
    (setf previous_window CurrentWindowDescriptor)
    (SelectWindow window)

    (!$DeleteBuffer)     % Kill everything in the buffer

    % Save the old label and then put strng into the per-(unframed)window
    % "label" variable.
    (setf old-label window_label)
    (setf window_label strng)
    (optional_refresh)   % Let the user see it!
    (return old-label)))