Language/OS - Multiplatform Resource Library/LANGUAGE OS.iso/scheme/pcscheme/geneva/sources.exe/SOURCES/EDWIN/INSERT80.S

Text File | 1993-06-15 | 4.9 KB | 146 lines

;;;
;;;    Copyright (c) 1985 Massachusetts Institute of Technology
;;;
;;;    This material was developed by the Scheme project at the
;;;    Massachusetts Institute of Technology, Department of
;;;    Electrical Engineering and Computer Science.  Permission to
;;;    copy this software, to redistribute it, and to use it for any
;;;    purpose is granted, subject to the following restrictions and
;;;    understandings.
;;;
;;;    1. Any copy made of this software must include this copyright
;;;    notice in full.
;;;
;;;    2. Users of this software agree to make their best efforts (a)
;;;    to return to the MIT Scheme project any improvements or
;;;    extensions that they make, so that these may be included in
;;;    future releases; and (b) to inform MIT of noteworthy uses of
;;;    this software.
;;;
;;;    3.  All materials developed as a consequence of the use of
;;;    this software shall duly acknowledge such use, in accordance
;;;    with the usual standards of acknowledging credit in academic
;;;    research.
;;;
;;;    4. MIT has made no warrantee or representation that the
;;;    operation of this software will be error-free, and MIT is
;;;    under no obligation to provide any services, by way of
;;;    maintenance, update, or otherwise.
;;;
;;;    5.  In conjunction with products arising from the use of this
;;;    material, there shall be no use of the name of the
;;;    Massachusetts Institute of Technology nor of any adaptation
;;;    thereof in any advertising, promotional, or sales literature
;;;    without prior written consent from MIT in each case.
;;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;
;;;    Modified by Texas Instruments Inc 8/15/85
;;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

;;;; These routines are implemented to get speed in character
;;;; insertion and deletions. They are written so as not to effect
;;;; the code too much.
;;;; Changes arise in the command for delete character and delete backward
;;;; character in allcoms.scm. Also, redisplay contains an statement for the
;;;; creation of the daemons.
;;;; These should be faster and should create less garbage.

(define region-insert-char!
  (lambda (mark char)
    (if (eq? char #\newline)
    (region-insert-newline! mark)
    (begin
      (if (group-read-only? (mark-group mark))
          (editor-error "Trying to modify read only text"))
      ((lambda (line pos)
         (%region-insert-char! line pos char))
       (mark-line mark) (mark-position mark))
      (%recompute-for-insert-del-char!  mark)))))

(define %region-insert-char!
  (letrec
    ((%receiver
    (lambda (mark cursor?)
      (if (or (> (mark-position mark) %pos)
          (and (= (mark-position mark) %pos)
               (mark-left-inserting? mark)))
          (set-mark-position! mark (1+ (mark-position mark))))))
     (%pos '()))

    (lambda (line pos char)
      (set! %pos pos)
      (for-each-mark! line %receiver)
      (line-insert-char! line pos char))))


(define %recompute-for-insert-del-char! '())

(define %create-char-daemon
  (lambda (window)
    (set! %recompute-for-insert-del-char!
      (%char-daemon window))))

(define (%char-daemon window)
  (lambda (mark)
    (let ((buffer (vector-ref window window:buffer))
      (table  (vector-ref window window:lines))
      (line   (mark-line mark))
      (y (line->y window (mark-line mark)))
      (y-size (vector-ref window window:y-size)))
      (let ((inferior (vector-ref table y)))
    (let ((old-ys (inferior:y-size inferior))
          (new-ys (find-y-size line)))
      (buffer-modified! buffer)
      (if (= old-ys new-ys)
          (begin
           (maybe-marks-changed window y)
           (set-start-end! window y y)
           (cursor-moved! window))
          (begin
           (if (< old-ys new-ys)
           (scroll-lines-down! window (- new-ys old-ys) y-size
                           table (+ (inferior:y-start inferior) old-ys))
           (scroll-lines-up! window (- old-ys new-ys) y-size
              table (+ (inferior:y-start inferior) old-ys)))
           (set-inferior:y-size! inferior new-ys)
           (fill-entries (1+ y)
                 (+ (inferior:y-start inferior) new-ys)
                 y table y-size)
           (set-start-end! window y (-1+ y-size))
           (everything-changed! window window-redraw!))))))))


(define %region-delete-char!
  (letrec
    ((%receiver
    (lambda (mark cursor?)
      (cond ((> (mark-position mark) end-pos)
         (set-mark-position! mark (- (mark-position mark)
                         offset)))
        ((> (mark-position mark) %pos)
         (set-mark-position! mark %pos)))))
     (%pos '())
     (end-pos '())
     (offset 1))

  (lambda (mark)
    (letrec
      ((%%region-delete-char!
     (lambda (line pos)
       (set! %pos pos)
       (set! end-pos (1+ pos))
       (for-each-mark! line %receiver)
       (subline-extract! line pos (1+ pos)))))

    (if (group-read-only? (mark-group mark))
    (editor-error "Trying to modify read only text"))
    (%%region-delete-char! (mark-line mark) (mark-position mark))
    (%recompute-for-insert-del-char! mark)))))