PrEd Release Notes
                 Versions 1.2D and 1.2BW
                     16 February 1990

                   Michael A. Covington
             Artificial Intelligence Programs
                 The University of Georgia
               Athens, Georgia 30602 U.S.A.


Overview

PrEd (Program Editor) was written for internal use at the
University of Georgia. It is distributed free of charge, and users are
invited to share it. PrEd is copyrighted and resale for more than
the cost of copying is prohibited.

PrEd is a general-purpose editor for ASCII text files. It is
especially suitable for environments where available memory is
limited, such as DOS shells under other pieces of software. PrEd
requires an IBM PC (or PS/2) or exact compatible with at least
55K of available memory.

PrEd is not a word processor. Although it can send portions of
files to the printer, it has no provision for page numbering,
formatting, or special printed effects such as boldface or
underlining.

PREDBW is a black-and-white version of PrEd, for laptop computers
and other computers with monochrome screens.



User Support

Because PrEd is distributed free, neither its author nor the
University derives any income from it. Because of this, we cannot
afford to return long distance calls or to spend substantial amounts
of time assisting users. Bona fide bug reports are always welcome.
So are suggestions, but remember that one of PrEd's design goals
is to be small, and this limits the range of features that can be
included.



Features of PrEd

-- Runs in very little memory (55K bytes)

-- Similar to the editor built into Turbo Pascal

-- Key assignments are a combination of those of WordStar and
   Word Perfect

-- Comprehensive menu-based help system

-- Automatic highlighting of matching parentheses

-- Can insert tabs and control characters into text


PrEd versus AHED

PrEd was written as a replacement for AHED (Ad Hoc Editor),
which requires 80K bytes to run. The user coming from AHED to
PrEd will notice the following major differences:

-- A few slightly different key assignments (resemblances to the
   IBM Personal Editor have been taken out)

-- Faster operation and many minor enhancements

-- Line length limit of about 250 bytes (AHED allows considerably
   longer lines)

-- File size limit of about 64K (AHED can edit larger files)

-- No margins or word wrap (in this respect, PRED is less like a
   word processor)

-- No multifile editing (PRED edits only one file at a time)

-- Menus disappear when you press Esc (AHED used Alt-A for
   this purpose)


Help System

The PrEd help system is designed to teach you the keystrokes, not
merely tell you about them. To select an editing action from a
menu, you hit exactly the same key that would perform the same
action if the menu were not on the screen.

To enter the help system, press F3.


Parenthesis Matching

PrEd will help you balance parentheses in complex expressions.

Whenever the cursor is on any of the closing delimiters

              )  ]  }  *)  */

PrEd will search for the corresponding opening symbol

              (  [  {  (*  /*

and display it in a different color.

There is a slight delay before this happens. The delay ensures that
the parenthesis matching routine will not interrupt you if you are
typing rapidly.

Parenthesis matching happens only if there is no marked block
being displayed. If you have marked a block, you can get rid of it
in either of two ways:

-- Make it empty by putting its end before its beginning; or

-- Hide (turn off) the marking by pressing ^K^H.

Either of these actions will enable parenthesis matching to proceed.


Revision History

Version 1.0 (June 1989)

-- First version of PrEd released for general distribution, although
   prototypes bearing the name PrEd were in use as much as a
   year earlier.

Version 1.1 (August 1989)

-- File is guaranteed to end with Return and Line Feed (as
   required by some compilers and interpreters). (To defeat this,
   go to the end of the file and press Ctrl-P Ctrl-Z, thereby
   inserting an explicit end-of-file mark where you want it.)

Version 1.2 (August 1989)

-- Major improvements to parenthesis matching system.

Version 1.2A (August 1989)

-- Marked-block color was changed to improve visibility on
   monochrome monitors attached to machines with CGAs in
   color mode.

Versions 1.2B (December 1990) and 1.2C (February 1991)

-- Various bug fixes. These versions were not widely distributed.

Versions 1.2D and 1.2BW (February 1991)

-- Minor improvements to help system, including documentation
   of Ctrl-U ("abort command") key.

-- Version 1.2BW (residing on file PREDBW.EXE) is designed for
   laptop computers with monochrome screens. It uses ordinary (non-
   highlighted) type for ordinary text regardless of video mode.