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Information about “MYSTIC PASCAL - PROGRAMERS UTILITY”
MYSTIC PASCAL is an integrated programming environment that rigidly
follows the ISO Pascal Standard.
MYSTIC PASCAL combines editing, compiling, program testing, and
debugging in to one unit. The traditional pattern of program
development -- the edit/compile/test cycle -- is greatly speeded up with
an integrated programming environment. You do not need to return to the
operating system and reload each program at each phase of the cycle.
MYSTIC PASCAL is an ``interactive compiler'' and can compile entire
Pascal source files. It also lets you key in Pascal statements, as well
as instantly compile and execute then at the global level. This is
similar to the Direct Mode of BASIC interpreters, with a critical
difference: MYSTIC PASCAL is a true object-code compiler. It is not an
interpreter or a pseudo-code compiler.
FILES.TXT
The files on this disk:
PAS?.DOC Documentation of the commands supported and their use.
TUTOR.DOC Documentation on TUTOR.PAS
TUTOR.PAS Pascal program demonstrating Mystic Pascal capabilities
MYSTIC.EXE Mystic Pascal Version 1.5
MYSTIC.LIB Mystic Pascal support library
MYSTICIN.EXE Mystic Pascal installation program
READ.ME Basic starting instructions
PROBLEM.FRM Form for reporting problems/bugs
COMMENT.FRM Form for suggesting features for future versions
REGISTRN.FRM Form for becoming a registered user
FILES.TXT This file
FILES965.TXT
Disk No: 965
Program Title: MYSTIC PASCAL
PC-SIG version: 1.1
MYSTIC PASCAL is an integrated programming environment that rigidly
follows the ISO Pascal Standard.
MYSTIC PASCAL combines editing, compiling and program testing and
debugging in one unit. The traditional pattern of program
development--the edit/compile/test cycle--is greatly speeded up with an
integrated programming environment. You do not need to return to the
operating system and reload each program at each phase of the cycle.
MYSTIC PASCAL is an "interactive compiler". MYSTIC can compile entire
Pascal source files like previous Pascals. It also allows Pascal
statements to be keyed in, instantly compiled and executed at the global
level. This is similar to the Direct Mode of BASIC interpreters, with a
critical difference: MYSTIC PASCAL is a true object-code compiler. It
is not an interpreter or a pseudo-code compiler.
Some of MYSTIC PASCAL's major features:
~ISO Standard Pascal Level 0 (MYSTIC PASCAL version 1.6)
~True 8086 object-code compiler
~Two level optimization
~Immediate compilation and execution of global Pascal statements
~Full-screen editor
~Help windows support full Pascal language
~Multi-tasking support
~Multiple video screens are maintained
~Program code up to one megabyte
~Program data up to one megabyte.
Usage: Integrated Program Environment.
Special Requirements: None.
How to Start: Type GO (press enter).
Suggested Registration: $10.00
File Descriptions:
REGISTRN FRM Form for becoming a registered user.
COMMENT FRM Form for suggesting features for future versions.
PROBLEM FRM Form for reporting problems/bugs.
PAS??? DOC Documentation for the program (9 files).
TUTOR PAS Pascal program demonstrating MYSTIC PASCAL capabilities.
TUTOR DOC Documentation on TUTOR.PAS.
READ ME Basic starting instructions.
MYSTICIN EXE MYSTIC PASCAL installation program.
MYSTIC LIB MYSTIC PASCAL support library.
MYSTIC EXE MYSTIC PASCAL version 1.5.
FILES TXT Listing of included files.
PC-SIG
1030D East Duane Avenue
Sunnyvale Ca. 94086
(408) 730-9291
(c) Copyright 1988 PC-SIG, Inc.
GO.TXT
╔═════════════════════════════════════════════════════════════════════════╗
║ <<<< Disk No 965 MYSTIC PASCAL >>>> ║
╠═════════════════════════════════════════════════════════════════════════╣
║ To print the documentation, Type: ║
║ COPY READ.ME LPT1: (press enter) then ║
║ COPY *.DOC (press enter) ║
║ ║
║ To run the program, Type: MYSTIC (press enter) ║
╚═════════════════════════════════════════════════════════════════════════╝
PAS1.DOC
M Y S T I C P A S C A L
U S E R
M A N U A L
Mystic Canyon Software
P.O.Box 1010
Pecos, New Mexico 87552
(505) 757-6344
Trust in the Lord with all your heart,
on your own intelligence rely not;
In all your ways be mindful of him,
and he will make straight your paths.
Proverbs 3:5-6
The beginning of wisdom is the fear of the Lord,
and knowledge of the Holy One is understanding.
Proverbs 9:10
Toil not to gain wealth,
cease to be concerned about it;
While your glance flits to it, it is gone!
for assuredly it grows wings,
like the eagle that flies toward heaven.
Proverbs 23:4-5
He who obeys the commandments he has from me
is the man who loves me;
and he who loves me will be loved by my Father.
I too will love him and reveal myself to him.
John 14:21
No sooner had he said this than he was lifted up
before their eyes in a cloud which took him from
their sight.
Acts 1:9
From about half past ten in the evening to
about half an hour after midnight.
Fire.
God of Abraham, God of Isaac, God of Jacob,
Not the God of philosophers and scholars.
Absolute Certainty: Beyond reason. Joy. Peace.
Forgetfulness of the world and everything but God.
The world has not known Thee, but I have known Thee.
Joy! joy! joy! Tears of joy!
Blaise Pascal
-- from a scrap of paper found
sewn up in his doublet after
his death.
COPYRIGHT
Copyright 1986 by Mystic Canyon Software.
All rights reserved. Version 1.5 is released to
shareware and may be copied and distributed,
provided the following conditions are met:
transcribed, stored in a retrieval
system, or translated into any
language or computer language, in
any form or by any means,
electronic, mechanical, magnetic,
optical, chemical, manual or
otherwise, without the prior written
permission of Mystic Canyon
Software, P.O.Box 1010, Pecos, New
Mexico 87552.
DISCLAIMER
Mystic Canyon Software makes no
representations or warranties with
respect to the contents hereof and
specifically disclaims any implied
warranties of merchantability or
fitness for any particular purpose.
Further, Mystic Canyon Software
reserves the right to revise this
publication and to make changes from
time to time in the content hereof
without obligation of Mystic Canyon
Software to notify any person of
such revision or changes.
TRADEMARKS
Mystic Pascal is a trademark of
Mystic Canyon Software. Wordstar is
a registered trademark of MicroPro
International Corp.
Mystic Pascal User Manual 1
1. Introduction. . . . . . . . . . . . . . . . . . . . . 4
1.1 Overview of Mystic Pascal . . . . . . . . . . . 6
1.2 System Requirements . . . . . . . . . . . . . . 8
1.3 List of Files . . . . . . . . . . . . . . . . . 8
1.4 Replacement Disks . . . . . . . . . . . . . . . 8
2. Operating Mystic Pascal . . . . . . . . . . . . . . . 9
2.1 Starting Mystic Pascal. . . . . . . . . . . . . 10
2.2 Screens . . . . . . . . . . . . . . . . . . . . 11
3. Full Screen Editor. . . . . . . . . . . . . . . . . . 12
3.1 Loading and Saving Pascal Programs. . . . . . . 13
3.2 Entering a New Pascal Program . . . . . . . . . 13
3.3 Editing Commands. . . . . . . . . . . . . . . . 14
3.3.1 Cursor Movement Commands . . . . . . . . 14
3.3.2 Scroll Commands. . . . . . . . . . . . . 14
3.3.3 Insert and Delete Commands . . . . . . . 14
3.4 Compiling a Pascal Program. . . . . . . . . . . 15
3.5 EXE File Create . . . . . . . . . . . . . . . . 15
4. Direct Mode . . . . . . . . . . . . . . . . . . . . . 16
4.1 Case Control. . . . . . . . . . . . . . . . . . 16
4.2 Video Snow. . . . . . . . . . . . . . . . . . . 17
4.3 Intermediate Code Listing . . . . . . . . . . . 17
4.4 Clear Screen Command. . . . . . . . . . . . . . 17
5. System Display. . . . . . . . . . . . . . . . . . . . 18
5.1 Storage Map . . . . . . . . . . . . . . . . . . 18
5.2 Process Control Table . . . . . . . . . . . . . 20
6. Help Windows. . . . . . . . . . . . . . . . . . . . . 21
7. Multi-tasking Support . . . . . . . . . . . . . . . . 22
7.1 Message Passing . . . . . . . . . . . . . . . . 23
7.2 START . . . . . . . . . . . . . . . . . . . . . 24
7.3 PRIORITY. . . . . . . . . . . . . . . . . . . . 25
7.4 QUEUE . . . . . . . . . . . . . . . . . . . . . 26
7.5 SEND. . . . . . . . . . . . . . . . . . . . . . 27
7.6 RECEIVE . . . . . . . . . . . . . . . . . . . . 28
8. Procedures and Functions. . . . . . . . . . . . . . . 29
8.1 ABS . . . . . . . . . . . . . . . . . . . . . . 30
8.2 ARCTAN. . . . . . . . . . . . . . . . . . . . . 31
8.3 CHR . . . . . . . . . . . . . . . . . . . . . . 32
8.4 COS . . . . . . . . . . . . . . . . . . . . . . 33
8.5 DISPOSE . . . . . . . . . . . . . . . . . . . . 34
8.6 EXP . . . . . . . . . . . . . . . . . . . . . . 35
8.7 FLOAT . . . . . . . . . . . . . . . . . . . . . 36
8.8 FRACTION. . . . . . . . . . . . . . . . . . . . 37
Table of Contents
Mystic Pascal User Manual 2
8.9 INTR. . . . . . . . . . . . . . . . . . . . . . 38
8.10 INTSTR . . . . . . . . . . . . . . . . . . . . 39
8.11 LN . . . . . . . . . . . . . . . . . . . . . . 40
8.12 NEW. . . . . . . . . . . . . . . . . . . . . . 41
8.13 ODD. . . . . . . . . . . . . . . . . . . . . . 43
8.14 OFFSET . . . . . . . . . . . . . . . . . . . . 44
8.15 ORD. . . . . . . . . . . . . . . . . . . . . . 45
8.16 PACK and UNPACK. . . . . . . . . . . . . . . . 46
8.17 PRED . . . . . . . . . . . . . . . . . . . . . 47
8.18 REALSTR. . . . . . . . . . . . . . . . . . . . 48
8.19 ROUND. . . . . . . . . . . . . . . . . . . . . 49
8.20 SEGMENT. . . . . . . . . . . . . . . . . . . . 50
8.21 SIN. . . . . . . . . . . . . . . . . . . . . . 51
8.22 SQR. . . . . . . . . . . . . . . . . . . . . . 52
8.23 SQRT . . . . . . . . . . . . . . . . . . . . . 53
8.24 STRINT . . . . . . . . . . . . . . . . . . . . 54
8.25 STRREAL. . . . . . . . . . . . . . . . . . . . 55
8.26 SUCC . . . . . . . . . . . . . . . . . . . . . 56
8.27 TRUNC. . . . . . . . . . . . . . . . . . . . . 57
8.28 UPCASE . . . . . . . . . . . . . . . . . . . . 58
9. Input/Output. . . . . . . . . . . . . . . . . . . . . 59
9.1 File Variables. . . . . . . . . . . . . . . . . 60
9.2 Standard Files. . . . . . . . . . . . . . . . . 60
9.3 How to Send Data to Your Printer. . . . . . . . 60
9.4 ASSIGN. . . . . . . . . . . . . . . . . . . . . 61
9.5 CLOSE . . . . . . . . . . . . . . . . . . . . . 62
9.6 EOF . . . . . . . . . . . . . . . . . . . . . . 63
9.7 EOLN. . . . . . . . . . . . . . . . . . . . . . 64
9.8 GET, PUT and Buffer Variables . . . . . . . . . 65
9.9 IORESULT. . . . . . . . . . . . . . . . . . . . 66
9.10 PAGE . . . . . . . . . . . . . . . . . . . . . 67
9.11 READ . . . . . . . . . . . . . . . . . . . . . 68
9.12 READLN . . . . . . . . . . . . . . . . . . . . 69
9.13 RESET. . . . . . . . . . . . . . . . . . . . . 70
9.14 REWRITE. . . . . . . . . . . . . . . . . . . . 71
9.15 SEEK . . . . . . . . . . . . . . . . . . . . . 72
9.16 WRITE. . . . . . . . . . . . . . . . . . . . . 73
9.17 WRITELN. . . . . . . . . . . . . . . . . . . . 74
10. MYSTICIN Installation Program . . . . . . . . . . . . 75
11. Programming Notes . . . . . . . . . . . . . . . . . . 76
Table of Contents
Mystic Pascal User Manual 3
Appendixes
A. Error Messages. . . . . . . . . . . . . . . . . . . . 79
B. ASCII Table . . . . . . . . . . . . . . . . . . . . . 80
C. ISO Standard Pascal . . . . . . . . . . . . . . . . . 81
Table of Contents
Mystic Pascal User Manual 4
1. Introduction
Mystic Pascal is an integrated programming environment for
the IBM Personal Computer and compatibles. Mystic Pascal rigidly
follows the ISO Pascal Standard.
Before the IBM PC, most personal computers were limited to
64K of main storage. Now most machines have 256K to 640K. Soon
most computers will have 640K or more. Newer machines will allow
up to 16 megabytes. (In March 1975 we purchased an Altair 8800
computer kit with 256 bytes of storage.)
This trend to larger memories permits major advances in
software. Business programs have evolved from word processors
and spreadsheets to "integrated software systems" - single large
programs combining many functions.
Mystic Pascal combines editing, compiling and program
testing and debugging in one unit. The traditional pattern of
program development - the edit/compile/test cycle - is greatly
speeded up with an integrated programming environment. You do
not need to return to the operating system and reload each
program at each phase of the cycle.
Mystic Pascal is an "interactive compiler". Mystic can
compile entire Pascal source files like previous Pascals. But it
also allows Pascal statements to be keyed in, instantly compiled
and executed at the global level. This is similar to the Direct
Mode of Basic interpreters, with a critical difference -- Mystic
Pascal is a true object code compiler. It is not an interpreter
or a pseudo-code compiler.
The Mystic Pascal compiler is based on a new type of
compiler technology. First, it is a multi-tasking compiler that
runs in the background while you are editing or doing other work.
Second, it is an incremental compiler. If you are working on a
5000 line program and modify 3 lines, it only needs to recompile
those three lines. If those lines contained variable
declarations, it will also recompile lines of code which
referenced those variables. It keeps track of all references
within the program. Third, Mystic Pascal is an optimizing
compiler.
Section 1: Introduction
Mystic Pascal User Manual 5
The highest priority in the design of Mystic Pascal was
speed - both compilation speed and execution speed. Here are
some of Mystic Pascal's major features:
-- ISO Standard Pascal Level 0 (Mystic Pascal version 1.6)
-- True 8086 object code compiler
-- Two level optimization
-- Immediate compilation and execution of global Pascal
statements
-- Full screen editor
-- Help windows support full Pascal language
-- Multi-tasking support
-- Multiple video screens are maintained
-- Program code up to 1 megabyte
-- Program data up to 1 megabyte
Section 1: Introduction
Mystic Pascal User Manual 6
1.1 Overview of Mystic Pascal
This is a technical overview of Mystic Pascal. Users who
have no interest in the internal structure of the system should
skip this section.
Mystic Pascal is an integrated programming environment. It
has several major components:
-- full screen editor
-- direct mode
-- system display
-- compiler
-- help facility
-- nucleus
Nucleus
The nucleus is an operating system extension which adds an
extra layer of functions to PC-DOS. It does not replace any
existing DOS functions. Many nucleus functions are accessed by
interrupt vectors. The nucleus supports these major functions:
-- process management - multitasking
-- queue management for interprocess communication
-- dynamic storage management
-- video screen management and window support
Each of the major system components is a separate process.
The components execute concurrently and may communicate with each
other through message queues. Some processes have their own
video screens. The user may switch among several screens via
function key 1 (F1). The screens not currently displayed are
stored in buffers.
Keyboard input is routed to the keyboard queue of the
process which owns the currently displayed video screen. The
process may read this queue as it needs input. Some special
keyboard inputs are intercepted by the nucleus and are not passed
on to active processes - F1 is one example.
Full Screen Editor
A full screen editor allows the user to enter new Pascal
programs and modify existing ones. From the editor screen Pascal
source files may be loaded from and saved to disk. The compiler
is also invoked from the editor screen via F2.
Compiler
Section 1: Introduction
Mystic Pascal User Manual 7
The compiler translates Pascal source programs into 8086
object code. The ISO Standard Pascal Level 0 language is
supported.
Besides compiling entire programs, single statements entered
in the Direct Mode screen may be compiled and immediately
executed.
Direct Mode
In the Direct Mode screen, Pascal statements may be directly
entered. These will be instantly compiled and executed. This
advanced feature allows interactive or exploratory programming in
a style similar to the Lisp and Forth languages.
System Display
The System Display screen shows the current system status
and time of day. A storage map and a table of process control
blocks are formatted. The display is updated approximately once
per second.
Help Facility
The Help facility process displays the Help menus in
windows and loads Help text from the system library.
Section 1: Introduction
Mystic Pascal User Manual 8
1.2 System Requirements
Mystic Pascal requires 256K or more of main storage and DOS
2.0 or higher. Because Mystic Pascal directly accesses the video
storage buffers, accesses the ROM BIOS, modifies interrupt
vectors and uses the 18 Hz timer, it may not function correctly
on IBM compatibles that are less than 100% compatible.
1.3 List of Files
The first thing you should do is make a backup copy of the
master disk. Do not use the master disk as your working disk.
The master disk does not contain a copy of the PC-DOS
operating system which is proprietary software. Do not try to
boot up the master disk.
MYSTIC.EXE The Pascal compiler system
MYSTIC.LIB Library of messages and help windows
MYSTICIN.EXE System installation program
TUTOR.PAS Mystic Pascal tutorial program
TUTOR.DOC Instructions for running TUTOR
PROBLEM.FRM Problem report form
1.4 Replacement Disks
After receiving Mystic Pascal, the first thing you should do
is backup the master disk. Do not use the master disk for your
working disk.
If you suspect that your master disk is damaged, try to copy
the files to another disk using the COPY command rather than
DISKCOPY. DISKCOPY copies the entire disk and would report all
errors found even if the bad section of the disk contains no
files.
If you are certain that your master disk is damaged and not
recoverable, we can provide a replacement. Pack the disk up and
ship it back to us. We must have the original master before we
will ship the replacement. There is no charge for replacement if
you return it within 15 days of receiving the package. If it is
beyond 15 days, include $10.00 to cover shipping and processing.
Also include a note indicating:
-- description of the problem, any error messages
-- type of computer
-- current shipping address
Section 1: Introduction
Mystic Pascal User Manual 9
2. Operating Mystic Pascal
Mystic Pascal is an "integrated programming environment."
This means that it combines in one large program several
components that were generally implemented as several smaller
programs in earlier Pascals.
The first component is the compiler itself which translates
Pascal source programs into 8086 object code. The second
component is the full screen editor which is used to modify
existing Standard Pascal programs or to create new ones.
Another component is the Direct Mode processor. This is
similar to Direct Mode in a Basic interpreter. You can enter
Pascal statements and they will be instantly compiled and
executed and any output will be displayed immediately. For
example, if your main Pascal program has declared a global
variable X1 as an Integer, you could enter in Direct Mode:
X1 := 75 {the value 75 is now stored in X1}
WRITELN( SQR(X1) ) {the square of 75 is displayed }
READ(INFILE, VALUE); WRITELN(VALUE) {multiple statements}
TUTOR {run a main program named TUTOR}
In Direct Mode, you may enter any legal Pascal statement.
The statement(s) you enter are inserted into a hidden anonymous
procedure, this procedure is compiled and then called. The
procedure is compiled as if it were placed immediately before the
main program BEGIN block -- you can access all global variables,
procedures and functions. Local variables, procedures and
functions may not be directly accessed from Direct Mode.
Section 2: Operating Mystic Pascal
Mystic Pascal User Manual 10
2.1 Starting Mystic Pascal
If you have not already done so, you should make a backup
copy of the Mystic Pascal master disk now.
Mystic Pascal may be placed on any diskette or hard disk
drive. MYSTIC.EXE is the main compiler system file. To start
Pascal enter:
MYSTIC
If MYSTIC.EXE is not on your currently logged disk, then you
must include a disk letter prefix. For example, if MYSTIC.EXE is
on your C: disk and you are logged into the A: disk, enter:
C:MYSTIC
When the compiler is starting up, it must locate the system
library file MYSTIC.LIB. It looks for the library on the current
disk. If it does not find it there, it asks you on which disk it
is located.
When Mystic Pascal starts it will display the opening screen
and then go to the editor screen. From the editor screen you can
load a Pascal program (function key 2) or go to any other screen
(function key 1).
Section 2: Operating Mystic Pascal
Mystic Pascal User Manual 11
2.2 Screens
Mystic Pascal maintains multiple video screens. The term
"screen" refers to a complete video page of 25 rows by 80
columns. The term "window" refers to a smaller rectangular
section of a screen.
Some major components of the integrated programming
environment have their own screens. The Editor and Direct Mode
processor are two examples. If you were working in the editor,
you could switch to Direct Mode, do some work in that screen, and
then return to the editor screen. It would appear exactly as it
did when you left it.
Screens which are not currently displayed are stored in
buffers in main storage. The cursor position is also saved.
Function key 1 (F1) is used to switch between screens. When
you press F1, a small menu window appears on the current screen.
The name of the current screen is flashing or otherwise
indicated. You then press another function key to select the
screen you want to go to. If you press any key not listed on the
menu the screen switch operation is cancelled.
Screen Selection
F1 Editor
F2 Direct Mode
F3 System Display
F4 Laser Display
Ctrl-End Exit
When the screen selection menu is displayed you may also
enter Ctrl-End to terminate Mystic Pascal and return to DOS.
Your programs and data will not be automatically saved.
The colors of the screens and help windows may be modified
by the Mysticin installation program. Also IBM Color card video
"snow" may be suppressed.
Section 2: Operating Mystic Pascal
PAS2.DOC
Mystic Pascal User Manual 12
3. Full Screen Editor
Mystic Pascal provides a full screen editor which is used
for entering, modifying and inspecting Pascal source programs.
It is not intended for editing other types of files.
You can edit your Pascal program as a text file although the
editor stores the program in a "tokenized" format. A token is a
one byte code which can represent an entire Pascal reserved word.
For example, the reserved word PROCEDURE uses 9 bytes in text
format but only one byte in token format. Obviously a typical
Pascal program can be greatly compressed by using token format.
The editor converts all identifiers to upper case when it
stores them in its table. You can use an option switch to
control whether reserved words, standard identifiers and user
defined identifiers are displayed in lower or upper case. (Refer
to section 4.1 of this manual.) For example, the two
identifiers "Initialize" and "INITIALIZE" are treated as the same
identifier.
Source programs must not contain lines greater than 80
characters, the width of the standard display screen.
Section 3: Full Screen Editor
Mystic Pascal User Manual 13
3.1 Loading and Saving Pascal Programs
When you want to work on a Pascal program which is saved on
disk, you must load it into Mystic Pascal. To load a program
from disk, go to the Editor screen. (F1 is used to switch
between the different screens.) If you are in the Editor, hit
F2. This will display the Editor command menu. Select command L
for load. You will be asked the name of the file to be loaded.
The 3 character filetype must be keyed in with the filename. It
does not assume any default filetype. A disk letter prefix may
be added to access files not on the current disk drive.
Sample filenames with filetypes:
TEST.PAS c:stock.mdl
Startrek.bak b:Train.set
If the file is not found or there is some other error, the
error message will be displayed and you may then retry the
operation.
To save a the Pascal program currently residing in the
editor is a nearly identical process. Enter F2, then S, then the
filename.filetype. The filename need not be the same as in the
last Load command.
3.2 Entering a New Pascal Program
When Mystic Pascal is first started the editor is empty and
a new program may be directly keyed in. If there is a program in
the editor and you wish to enter a new program, key F2, then N.
This command clears out the editor. Any program in the editor
buffer is cleared out of the buffer by the New command. You can
use the Save command to save such a program first.
Section 3: Full Screen Editor
Mystic Pascal User Manual 14
3.3 Editing Commands
Mystic Pascal editing commands are used to modify text on
the CRT screen for the current Pascal program. Many people are
experienced with the Wordstar word processing program. Mystic
Pascal's edit commands are similar to those commands.
3.3.1 Cursor Movement Commands
right one character Control D right arrow
left one character Control S left arrow
up one line Control E up arrow
down one line Control X down arrow
right one word Control F Control right arrow
left one word Control A Control left arrow
top of file Home
end of file End
tab Tab
reverse tab Shift Tab
next line return
3.3.2 Scroll Commands
scroll up one line Control Z
scroll down one line Control W
scroll up one page Control C PgUp
scroll down one page Control R PgDn
3.3.3 Insert and Delete Commands
insert mode toggle Control V Ins
insert new line Control N
delete character Control G Del
destructive backspace Control H right arrow key 14
delete word right Control T
delete line Control Y
Section 3: Full Screen Editor
Mystic Pascal User Manual 15
3.4 Compiling a Pascal Program
To compile a Pascal program you must first load it into the
editor. Generally a program you are working on will already be
in the editor.
Once your program is loaded and you are in the editor
screen, then to compile the program, enter key F2 then letter C.
If the compile has no errors, a small window will display the
elapsed time of the compile and the compiler speed in lines per
second. The size of the code generated is also displayed. Hit
any key to remove the window.
To compile, enter
F2 then C
If there is an error during the compile, the cursor is
positioned at the location of the error (or just past it) in the
source program. An error message is displayed in a small window.
Hit any key to remove the window and resume editing. Correct the
error and you can then recompile.
Technical Notes
Mystic Pascal uses an advanced compiler architecture to
achieve very high compile speed. The "Lines per second" value is
intended to show the effective compilation speed for comparison
with other compilers.
The compiler elapsed time is measured using the Personal
Computer's timer tick interrupt which occurs every 0.055 second
(18.2 times per second). If, by chance, no timer ticks occur
between the start and finish of the compilation, then the actual
time must have been between 0.0 and 0.055 second. In this case,
the elapsed time is adjusted to 0.030 second, a middle value, to
avoid division by zero in computing the lines per second.
3.5 EXE File Create ** 1.6 **
After a Pascal program has successfully compiled, a
standalone EXE file version of the program may be created with
the 'E' command on the F2 menu.
Section 3: Full Screen Editor
Mystic Pascal User Manual 16
4. Direct Mode
In the Direct Mode screen, Pascal statements may be entered
directly. They are instantly compiled, executed and any results
displayed.
The statements are compiled at the global level. You can
access all global variables, procedures and functions but not
those declared within a procedure or function. Each statement
must fit on one line. Multiple statements may be entered on one
line.
The backslash "\" is the prompt character.
To run the entire program, type the program's name which is
declared in the program header.
Since many Direct Mode statements will use the procedure
WRITE to display the value of variables, an abbreviated form is
provided.
.X, Y, Z is equivalent to
WRITE(X, Y, Z)
When using the dot print command, no other statements must
appear on the line and the dot must be the first character.
4.1 Case Control
The #CASE command controls the display of upper and lower
case in the editor screen and for the Save command. Three types
of words - reserved words, predefined identifiers and user-
declared identifiers - may be displayed in either upper or lower
case. The #CASE command is keyed into the Direct Mode screen.
The format is:
#CASE=abc
a, b and c may be either 'U' or 'L'. No spaces or commas
are allowed in this command.
a = reserved word case
b = predefined identifiers case
c = user-declared identifiers case
The initial setting is #CASE=ULL.
Section 4: Direct Mode
Mystic Pascal User Manual 17
4.2 Video Snow
The IBM Color Adapter may produce video noise or "snow" when
the video memory is directly updated. Mystic Pascal does access
the video memory directly because this is many times faster than
operating through DOS. Mystic Pascal is able to suppress the
snow effect, but this may greatly slow down the display speed
since screen updates may only be done during vertical retrace.
Snow suppression is automatically turned on when running on
the Color card. Snow suppression may be suppressed by the
Mysticin installation program, because some IBM compatible color
cards do not produce snow and should not be forced to pay the
speed penalty.
Snow suppression may also be toggled on and off with the
#SNOW command in Direct Mode. Do not use this command if a color
card is not present! Color card users can easily see the effect
of snow suppression by trying this command and then examining the
System Display screen.
4.3 Intermediate Code Listing
The Mystic Pascal compiler parser outputs intermediate
codes. The code generator then converts these "icodes" into 8086
object code. Mystic's first optimizer operates on the icodes and
the second optimizer operates on the 8086 code.
The #LIST command produces a listing of the icodes on the
printer. This listing is only for informational purposes for
hackers and other curious people.
The formats are:
#LIST = 1 Turn on Icode listing
#LIST = 0 Turn off Icode listing
Warning! The Icode listing for a large program can be VERY
long and may not be interrupted once begun.
4.4 Clear Screen Command
In Direct Mode the screen may be cleared by entering '#'
followed by a return.
Section 4: Direct Mode
PAS3.DOC
Mystic Pascal User Manual 18
5. System Display
The System Display screen contains technical information
about the current state of the Mystic Pascal system. This
information is useful in storage allocation with the installation
program and when working with multi-tasking programs.
This screen displays the current time-of-day (The PC's
onboard clock should be correctly set.) and the elapsed time
since Pascal was started. A storage map and a table of the
currently active processes are also displayed. The Display
Screen is updated approximately once every second when it is
being displayed.
5.1 Storage Map
The storage map shows the several main storage areas used by
Mystic Pascal. The starting address of each area is shown as an
absolute 20 bit (5 hex digit) number. This information can be
useful when using the Install program to modify the storage
configuration.
User Area
The user area is reserved for variables declared in the
user's program. Both global variables and procedures' local
variables are allocated in this region. Pointer variables
allocated with the NEW procedure are placed in Dynamic Storage,
not here.
Laser
The large area code-named "Laser" contains the internal
symbolic representation of the Pascal program. Compiled object
code and dynamic variables allocated with the NEW procedure are
also stored here. The Laser may be up to a maximum of 640K in
size. The percent of this area which is currently allocated is
displayed.
Dynamic Storage
Queue messages and various system control blocks are stored
in this area. Dynamic storage may be up to 60K in size. The
percent of this area which is currently allocated is displayed.
Section 5: System Display
Mystic Pascal User Manual 19
Feature Buffer
This buffer is used by the advanced feature support.
Screen Buffers
The non-displayed CRT screens are stored in this buffer
area.
Optimizer Buffer
The optimizer stores object code in this area during its
processing.
System Stack
This is the 8086 stack segment. A separate stack area is
maintained for each concurrently executing process.
System Data
This is the main 8086 data segment.
System Code
This is the 8086 code segment containing the nucleus and
compiler assembly code.
Program Segment Prefix
This 100H byte area is setup by DOS when Mystic Pascal is
started. It contains DOS system data areas and is not directly
used by Mystic Pascal.
Section 5: System Display
Mystic Pascal User Manual 20
5.2 Process Control Table
This is a display of the process control blocks (PCB) for
each process currently allocated. Seven data fields are
displayed.
The nucleus' process manager maintains a "pseudo-timer".
This is a 16 bit counter which is incremented whenever the
dispatcher transfers control to another process. The value of
the pseudo-timer is stored in a process control block when that
process is dispatched. This provides a very fast method of
keeping track of how recently each process has been dispatched.
When the pseudo-timer wraps around to 0, all PCB timer fields are
also reset to 0.
The dispatcher can use this information to give preference
to those processes that have been waiting a relatively long time
for a chance to execute. Each process is assigned a static
priority which is also considered by the dispatcher in selecting
a ready process.
Process
Name of the process.
St
Process current state
P = Pascal process STARTed by user
R = ready
W = waiting for queue message
Count
The number of times the process has been dispatched.
SP
The process's stack pointer.
Time
The pseudo-timer value when the process was last dispatched.
Pr
The static priority of the process. This value determines
what proportion of the processor time this process receives if it
is ready to execute.
Dyn
The dynamic priority of the process. This value actually
determines which ready process will be next dispatched. This
value is equal to:
static_priority + (current_pseudo_timer - time)
Section 5: System Display
Mystic Pascal User Manual 21
6. Help Windows
The Help facility is included in Mystic Pascal to make
learning easier for students and to provide a very fast reference
source for experienced Pascal users. The Help facility is always
available from any screen. Four function keys are used for help:
F7 Pascal Language Help
F8 Standard Procedures & Functions Help
F9 Editor Help
F10 Function Key Help
F7 Pascal Language Help
Function key F7 will display a menu window showing the Help
windows available. Enter the letter or number key to select the
topic you want to see.
Enter any character to leave a topic window and enter any
non menu character to leave the menu and return to the underlying
screen.
F8 Standard Procedures & Functions Help
Function key F8 displays a menu window showing all builtin
procedures and functions. Enter the letter or number to select
the topic you want to see
F9 Editor Help
Function key F9 displays a list of editor commands directly.
Hitting any key will remove the display.
F10 Function Key Help
Function key F10 displays a list of all function key
assignments. This is only a reminder list. The other function
keys may not be invoked directly from this display window.
Section 6: Help Windows
PAS4.DOC
Mystic Pascal User Manual 22
7. Multi-tasking Support
Mystic Pascal is a multi-tasking system. The editor,
compiler, system display and other major components are processes
which execute concurrently. Pascal programs may also use multi-
tasking.
In Mystic Pascal any global procedure may be started as an
independent process by the START builtin procedure. Up to 50
Pascal procedures may execute concurrently. The system
automatically switches among the concurrent procedures as they
execute. Procedures are allowed to execute if they are not
in a wait state and based on their static priority and the length
of time they have been waiting. Even the lowest priority
procedure will execute.
Concurrent procedures will run until the final END is
reached. At that time the process will be deleted. The same
Pascal source procedure may be started more than once -- a single
source procedure may have many incarnations. Concurrent
procedures may be recursive, may call global procedures, may
access global variables and may START global procedures.
Section 7: Multi-tasking Support
Mystic Pascal User Manual 23
7.1 Message Passing
Concurrent procedures may communicate by passing messages.
Messages are processed by Mystic Pascal's queue management
system. This is not only for communication but also allows
efficient synchronization among the concurrent procedures --
attempting to receive a message from an empty queue causes the
procedure to enter a wait state until a message arrives.
Queues are first-in-first-out (FIFO) storage mechanisms.
The queue messages are stored in the dynamic storage area.
As an example, consider a concurrent procedure LOG whose
purpose is to write one line messages to a printer. LOG must
accept messages from several other concurrent procedures. LOG
has its own input queue from which it receives messages and to
which other procedures send messages. LOG can ensure that only
one user at a time (itself) does printing. If several procedures
could print at the same time, their messages could become
interleaved resulting in a garbled printout.
PROCEDURE LOG;
LABEL 100;
BEGIN
QUEUE('LOGQ ');
100: RECEIVE('LOGQ ', MSG);
{print the message}
GOTO 100;
END;
Careful planning is necessary when concurrent procedures may
access a printer, console or disk files at the same time. Having
one concurrent procedure handle all accesses is a common solution
to this issue. This is related to the concept of a "monitor."
Before a queue may be used, it must be created by the QUEUE
builtin procedure. Each queue must have a unique 8 byte name.
The builtin queue management procedures are:
QUEUE create a new queue
SEND store a message on a queue
RECEIVE get a message from a queue
Section 7: Multi-tasking Support
Mystic Pascal User Manual 24
7.2 START
START( procedure_name, process_name, stack_size );
The START procedure is used to initiate a concurrent
procedure. The procedure will execute as a separate process
until it terminates by reaching its final END.
The process_name is an 8 character ASCII field. This name
is displayed in the system display and is used in the PRIORITY
builtin procedure. A single Pascal procedure may be started
several times. Each start must use a unique process name.
The stack_size is an integer expression. It specifies the
amount of space to be allocated in paragraphs - multiples of 16
bytes. Enough space must be included for this procedure's local
variables, the local variables of all procedures it calls and
additional stack space for evaluating expressions.
If the concurrent procedure is recursive or calls any
recursive procedures, great caution should be used in estimating
the stack_size or an insufficient storage run-time error may
result.
The priority of a concurrent procedure is initially set to
20. This may be modified by the PRIORITY builtin procedure.
START( LOG, 'LOGPROC ', 30 );
START( PRINTER, 'PRINTER ', 100 );
START( DOWJONESPORT, 'DJP ', 200 );
Section 7: Multi-tasking Support
Mystic Pascal User Manual 25
7.3 PRIORITY ** 1.6 **
PRIORITY( process_name, priority );
The PRIORITY procedure is used to modify the static priority
of a concurrent procedure which has been started. The initial
priority is 20. The priority parameter is an integer expression
in the range 1 to 64.
PRIORITY( 'LOGPROC ', 10 );
PRIORITY( 'DJP ', 64 );
PRIORITY( 'CHESS A ', 40 );
PRIORITY( 'CHESS B ', 35 );
Section 7: Multi-tasking Support
Mystic Pascal User Manual 26
7.4 QUEUE ** 1.6 **
QUEUE( queue_name );
The QUEUE procedure creates a new queue for message passing.
Each queue is identified by a unique 8 byte queue name. This
name does not have to be ASCII.
QUEUE( 'LOGQ ' );
QUEUE( 'ERRORMSG' );
QUEUE( 'COMMANDS' );
Section 7: Multi-tasking Support
Mystic Pascal User Manual 27
7.5 SEND ** 1.6 **
SEND( queue_name, variable );
The SEND procedure stores a message on a queue. The queue
must have been created by the QUEUE procedure.
The concurrent procedure that issues the SEND will resume
execution immediately unless the space allowed for this queue is
full. Then the issuer is placed in a wait state until space is
released by another concurrent procedure removing messages from
the queue.
SEND('RED ALRT','EEG INPUT CORRELATES 1.0 WITH PREDICTION');
SEND( 'TREESORT', ROOTPTR );
SEND( 'COMPILER', SOURCEARRAY );
Section 7: Multi-tasking Support
Mystic Pascal User Manual 28
7.6 RECEIVE ** 1.6 **
RECEIVE( queue_name, variable );
The RECEIVE procedure removes the oldest message from the
specified queue. If no messages are present, the issuer is
placed in a wait state until a message arrives.
RECEIVE( 'PRINTER ', OUTPUTLINE );
RECEIVE( 'BROKER3 ', STOCKORDER );
RECEIVE( 'EDITOR ', COMMAND );
Section 7: Multi-tasking Support
PAS5.DOC
Mystic Pascal User Manual 29
8. Procedures and Functions
This section of the manual describes procedures and
functions. Procedures and functions which are used in
Input/Output processing are described in section 9. Multi-
tasking procedures are described in section 7.
Procedure Purpose
--------- -------
DISPOSE deallocate dynamic variable
+ INTR interrupt call
NEW allocate dynamic variable
PACK unimplemented
UNPACK unimplemented
Function Return Value
-------- ------------
ABS absolute value
ARCTAN arctangent
CHR convert integer to character
COS cosine
EXP exponential function
+ FLOAT convert integer to real
+ FRACTION fractional part of real
+1.6 INTSTR convert integer to string
LN natural logarithm
ODD test for odd integer
+ OFFSET offset of a variable
ORD convert ordinal to integer
PRED preceding ordinal
+1.6 REALSTR convert real number to string
ROUND convert real number to integer
+ SEGMENT segment of a variable
SIN sine
SQR square
SQRT square root
+1.6 STRINT convert string to integer
+1.6 STRREAL convert string to real number
SUCC succeeding ordinal
TRUNC convert real number to integer
+1.6 UPCASE convert char to upper case
Section 8: Procedures and Functions
Mystic Pascal User Manual 30
8.1 ABS
ABS( expression )
The ABS standard function returns the absolute value of an
integer or real expression. The result is of the same type as
the input expression.
Examples:
A := ABS( X );
WRITELN( 'ABSOLUTE VALUE IS',ABS( COS( Y )));
B := ABS( X + Y / Z );
Section 8: Procedures and Functions
Mystic Pascal User Manual 31
8.2 ARCTAN
ARCTAN( expression )
This standard function returns the arctangent of a real or
integer expression. The result type is real and is expressed in
radians.
Examples:
WRITELN( ARCTAN( A + 3.14159 ));
NODE.VALUE := OLDNODE.VALUE + ARCTAN( V );
Section 8: Procedures and Functions
Mystic Pascal User Manual 32
8.3 CHR
CHR( integer_expression )
The CHR standard function converts an integer expression
into a character. The result type is char. If the integer
expression is less than zero or greater than 255, a run-time
error occurs.
CHR is often used for sending control characters to output
devices.
Examples:
WRITE( CHR( 12 ));
TAB := CHR( 9 );
CARRIAGERETURN := CHR(13);
LINEFEED := CHR(10);
Section 8: Procedures and Functions
Mystic Pascal User Manual 33
8.4 COS
COS( expression )
The COS standard function returns the cosine of a real or
integer expression whose value is given in radians. The result
type is real.
Examples:
WRITELN( COS( ANGLE ));
NODE.COSINE := COS( N );
WRITELN( COS( VELOCITY / CHARGE ));
Section 8: Procedures and Functions
Mystic Pascal User Manual 34
8.5 DISPOSE
DISPOSE( pointer_variable )
The DISPOSE procedure is used to deallocate dynamic
variables. The pointer_variable addresses a dynamic variable in
dynamic storage. After execution of the procedure the space
released is available for other uses.
Mystic Pascal supports true dynamic storage with auto-
compression. When blocks are freed up, storage fragmentation
occurs -- unused blocks tend to accumulate. Because many blocks
tend to be small, they cannot be immediately reused for another
purpose. When storage becomes short an auto-compression is
initiated by the Pascal system.
Example:
PROCEDURE DISPOSEDEMO;
TYPE
DYNVAR = ARRAY [1..200] OF CHAR;
VAR
POINTER : ^DYNVAR;
BEGIN
NEW( POINTER ); (* ALLOCATE A DYNAMIC VAR *)
(* DO SOME PROCESSING WITH THE DYNAMIC VAR *)
DISPOSE( POINTER ); (* FREE UP THE 200 BYTES *)
END;
Section 8: Procedures and Functions
Mystic Pascal User Manual 35
8.6 EXP
EXP( expression )
The exponential function computes e to the x power, where x is a
real or integer expression. The result type is real.
Examples:
X := EXP( Y );
SHIPVELOCITY := EXP( WARPFACTOR );
Section 8: Procedures and Functions
Mystic Pascal User Manual 36
8.7 FLOAT (Non-Standard Feature)
FLOAT( integer_expression )
The Float function converts integers to real numbers. The
result type is real.
Section 8: Procedures and Functions
Mystic Pascal User Manual 37
8.8 FRACTION (Non-Standard Feature)
FRACTION( real_expression )
The Fraction function returns the fractional part of a real
number. The result type is real.
Section 8: Procedures and Functions
Mystic Pascal User Manual 38
8.9 INTR (Non-Standard Feature)
INTR( interrupt, registers )
The INTR procedure permits access to DOS and BIOS functions
by directly calling interrupt routines. The standard DOS
interrupt is number 33. The interrupt number must be an integer
expression. The registers variable is used to set the 8086
registers on entry and they are stored into the variable on
return from the interrupt routine.
Registers is declared as:
REGISTERS = RECORD
AX,BX,CX,DX,BP,SI,DI,DS,ES,FLAGS : INTEGER
END;
Section 8: Procedures and Functions
Mystic Pascal User Manual 39
8.10 INTSTR (Non-Standard Feature) ** 1.6 **
INTSTR( integer )
The Intstr function converts an integer to a string. The
result type is
PACKED ARRAY [1..6] OF CHAR
The characters are right aligned in the field.
CHART.XAXIS[I] := INTSTR( I * DELTA );
REPORT.YEAR1 := INTSTR( YR );
Section 8: Procedures and Functions
Mystic Pascal User Manual 40
8.11 LN
LN( expression )
The LN function computes the natural logarithm of a real or
integer expression. If the expression is less than or equal to
zero a run-time error occurs. The result type is real.
Examples:
X := LN( Y );
WRITELN( LN( X + SQR(Y)));
IF LN( FACTORBETA ) < 0.1 THEN
WRITELN(FACTORBETA);
A := SQRT( LN(Z));
Section 8: Procedures and Functions
Mystic Pascal User Manual 41
8.12 NEW
Format 1
NEW( pointer_variable )
Format 2
NEW( pointer_variable, tag1,..., tagn )
The NEW procedure allocates new dynamic variables. A block
of dynamic storage of the required size is obtained. The block's
indirect address, not its actual address is stored in the pointer
variable.
After NEW has been executed, the dynamic variable may be
accessed. Dynamic variables remain allocated until specifically
deallocated by the DISPOSE procedure. If a procedure uses NEW to
allocate a dynamic variable, that variable remains allocated
after the procedure ends.
Format 2 contains 1 to n tag fields. These are the fields
specified in the CASE clause of variant records.
Section 8: Procedures and Functions
Mystic Pascal User Manual 42
Example:
(* PROGRAM FRAGMENT TO ALLOCATE A
LINKED LIST OF VARIABLE LENGTH.
THE ROOT OF THE LIST IS A GLOBAL
VARIABLE. NODES AFTER THE FIRST
ARE INSERTED BETWEEN THE ROOT AND
THE FIRST NODE. *)
TYPE
NODE = RECORD
NEXT : INTEGER;
DATA : REAL
END;
VAR
ROOT : ^NODE;
PROCEDURE LINKEDLIST ( COUNT : INTEGER );
VAR
I : INTEGER;
TEMP : ^NODE;
BEGIN
(* ALLOCATE FIRST NODE *)
NEW( ROOT );
(* SET END_OF_LIST INDICATOR *)
ROOT^.NEXT := NIL;
(* ALLOCATE LINKED LIST *)
FOR I := 1 TO COUNT DO
BEGIN
NEW( TEMP );
TEMP^.NEXT := ROOT;
ROOT := TEMP
END
END; (* LINKEDLIST *)
Section 8: Procedures and Functions
Mystic Pascal User Manual 43
8.13 ODD
ODD( integer_expression )
ODD is a Boolean function which returns the value true if
the integer_expression is odd otherwise it returns false.
The expression X is odd if (abs(X) mod 2) equals one.
Examples:
IF ODD(X) THEN TESTFORPRIME(X);
IF ODD(I) THEN I:=I+1;
WRITELN( ODD(Y) );
Section 8: Procedures and Functions
Mystic Pascal User Manual 44
8.14 OFFSET (Non-Standard Feature)
OFFSET( variable )
The Offset function returns the offset of a variable. Used
with the Segment function, this allows passing parameters such as
strings of characters to DOS with the INTR procedure. The result
type is integer.
Section 8: Procedures and Functions
Mystic Pascal User Manual 45
8.15 ORD
ORD( ordinal_expression )
The ORD function converts an ordinal value to an ordinal
number. For example, if
TYPE DAYS = (SUN,MON,TUE,WED,THU,FRI,SAT);
then ORD(TUE) is equal to 2.
Example:
REPEAT
READ(INFILE, CH);
WRITE( CH )
UNTIL ORD(CH) = 26; (* EOF CHAR DETECTION *)
(* ASCII DISPLAY *)
FOR CH := ' ' TO 'z' DO
WRITELN( CH, ' = ',ORD(CH));
Section 8: Procedures and Functions
Mystic Pascal User Manual 46
8.16 PACK and UNPACK
The PACK and UNPACK Pascal standard procedures are not used
in Mystic Pascal. A Pascal program may contain these procedures
but they will be treated as null operations.
Section 8: Procedures and Functions
Mystic Pascal User Manual 47
8.17 PRED
PRED( ordinal_expression )
The PRED function is the inverse of the SUCC function. The
predecessor function returns the ordinal value that is one less
than the input expression.
The PRED of 8 is 7. The PRED of 'T' is 'S'.
Example:
WRITELN( A, PRED(A) );
WRITELN( CH, PRED(CH) );
Section 8: Procedures and Functions
Mystic Pascal User Manual 48
8.18 REALSTR (Non-Standard Feature) ** 1.6 **
REALSTR( real_expression, mode, width, frac );
The Realstr function converts real numbers to strings. All
four parameters must always be present. The mode, width and frac
parameters are all integer expressions. Three conversion modes
are available.
Mode=0 Simple mode - no leading blanks, no trailing zeros,
exponent field is displayed only if required
Mode=1 Floating Point mode - width parameter specifies result
size.
Mode=2 Fixed Point mode - width parameter specifies result size
and frac parameter specifies number of fractional digits.
EDITAREA := REALSTR( AMOUNT, 2, 10, 4 );
FIELD4 := REALSTR( TOTAL, 0, 0, 0 );
Section 8: Procedures and Functions
Mystic Pascal User Manual 49
8.19 ROUND
ROUND( real_expression )
ROUND is a standard function which converts a real
expression to an integer value. If X >= 0 then ROUND(X) is
TRUNC(X + 0.5). If X < 0 then ROUND(X) is TRUNC(X - 0.5).
ROUND( 2.5 ) is 3
ROUND( -2.5 ) is -3
If the real value is too large to be converted to integer
format a run-time error occurs.
Examples:
INT := ROUND( X + Y );
TEMPERATURE := ROUND( THERMOMETERREADING );
PLOTX := ROUND( X / SCALINGFACTOR );
Section 8: Procedures and Functions
Mystic Pascal User Manual 50
8.20 SEGMENT (Non-Standard Feature)
SEGMENT( variable )
The Segment function returns the segment address of a
variable. For global variables this is the same as the User
Area. For local variables this will be a value inside the User
Area. Used with the Offset function this allows passing
parameters such as strings of characters to DOS with the INTR
procedure. The result type is integer.
Section 8: Procedures and Functions
Mystic Pascal User Manual 51
8.21 SIN
SIN( expression )
The SIN standard function returns the sine of a real or
integer expression whose value is given in radians. The result
type is real.
Examples:
WRITELN( SIN( ANGLE ));
NODE.SINE := SIN( N );
WRITELN( SIN( VELOCITY / CHARGE ));
Section 8: Procedures and Functions
Mystic Pascal User Manual 52
8.22 SQR
SQR( expression )
The SQR standard function computes the square of a real or
integer expression. The result type is of the same type as the
input expression.
Examples:
WRITELN( 'SQUARE OF X IS ', SQR(X) );
AREA := SQR( SIDE );
CIRCLEAREA := PI * SQR( RADIUS );
ENERGY := MASS * SQR( LIGHTSPEED );
Section 8: Procedures and Functions
Mystic Pascal User Manual 53
8.23 SQRT
SQRT( expression )
This standard function returns the square root of a real or
integer expression. The result type is real and is always a
positive value. A run-time error occurs if the input expression
is negative.
Examples:
WRITELN( SQRT( A + 3.14159 ));
NODE.VALUE := OLDNODE.VALUE + SQRT( V );
Section 8: Procedures and Functions
Mystic Pascal User Manual 54
8.24 STRINT (Non-Standard Feature) ** 1.6 **
STRINT( string )
The Strint function converts a string to an integer. If the
string does not contain a valid integer as its first non-blank
characters, a value of -32768 is returned.
VALUE := STRINT( INPUTSTRING );
X := STRINT( GETNUM );
Section 8: Procedures and Functions
Mystic Pascal User Manual 55
8.25 STRREAL (Non-Standard Feature) ** 1.6 **
STRREAL( string )
The Strreal function converts a string to a real number. If
the string does not contain a valid real number as its first non-
blank characters, a value of -9.999E-30 is returned.
A := STRREAL( TEXTVALUE );
X := STRREAL( VECTOR[ J ] );
Section 8: Procedures and Functions
Mystic Pascal User Manual 56
8.26 SUCC
SUCC( ordinal_expression )
The successor function is the inverse of the PRED function.
The SUCC function takes an ordinal value and returns the ordinal
value one greater.
The SUCC of 7 is 8. The SUCC of 'S' is 'T'.
Example:
WRITELN( A, SUCC(A) );
WRITELN( CH, SUCC(CH) );
Section 8: Procedures and Functions
Mystic Pascal User Manual 57
8.27 TRUNC
TRUNC( real_expression )
TRUNC is a standard function which converts a real
expression to an integer value. The fractional portion of the
real expression is truncated.
TRUNC(2.5) is 2
TRUNC(-2.5) is -2
If the real value is too large to be converted to integer
format a run-time error occurs.
Examples:
INT := TRUNC( X + Y );
TEMPERATURE := TRUNC( THERMOMETERREADING );
PLOTX := TRUNC( X / SCALINGFACTOR );
Section 8: Procedures and Functions
Mystic Pascal User Manual 58
8.28 UPCASE (Non-Standard Feature) ** 1.6 **
UPCASE( expression )
The UPCASE function is a Mystic Pascal extension which
converts a char or string expression to upper case. The result
type is the same as the input expression type.
Examples:
IF UPCASE( COMMAND ) = 'X' THEN
CMDX;
WRITE( F1, UPCASE(NAME) );
READLN( OPTION );
IF UPCASE( OPTION ) = 'EXIT' THEN GOTO 99;
Section 8: Procedures and Functions
PAS6.DOC
Mystic Pascal User Manual 59
9. Input/Output
Mystic Pascal supports all standard Pascal I/O procedures
and functions and has extensions to support random disk file
access and to assign a DOS file name to a Pascal file variable.
+ ASSIGN associate a file name with a file variable
+ CLOSE terminate processing on a file
EOF Boolean function indicates end-of-file
condition
EOLN Boolean function indicates end-of-line
condition for text files
1.6 GET move file pointer to next component
+ IORESULT integer function status of I/O operation
PAGE advance textfile output to new page
1.6 PUT append buffer variable to file
READ obtain input from console or disk file
READLN obtain textfile input from new line
RESET prepare an existing file for input
REWRITE create a file for output
+ SEEK position the file pointer for random access
WRITE output data to console, printer, disk file
WRITELN output textfile data and terminate line
Section 9: Input/Output
Mystic Pascal User Manual 60
9.1 File Variables
File variables, like other variables, are declared in a VAR
section. They indicated the data type of the file's components.
TYPE
DATAFILE = FILE OF REAL;
VAR
F1 : DATAFILE;
F2 : FILE OF ARRAY [0..63] OF CHAR;
F3 : TEXT;
Textfiles are declared by the predefined type TEXT.
Textfiles consist of lines of characters separated by the end-of-
line byte sequence 0DH, 0AH (carriage return, line feed).
9.2 Standard Files
The DOS operating system supports several standard "files"
or logical devices which are always available. These may be used
directly as file variables in Read/ln and Write/ln. They may
also be assigned to Pascal file variables by the Assign
procedure.
CON standard console device (input/output)
KBD keyboard device (input without echoing)
AUX auxiliary device (input/output)
LST printer (output)
PRN printer (output)
If no file variable is specified as the first parameter in
the Read/ln or Write/ln procedures, the default files INPUT and
OUTPUT respectively are used. These are assigned to the standard
console and keyboard devices.
9.3 How to Send Data to Your Printer
To route output to your printer specify the Standard File
LST or PRN in your WRITE or WRITELN statements.
WRITELN( PRN, 'This line will be printed.');
WRITE( PRN, 'X =',X,' Y =',Y,' Z =',Z );
Section 9: Input/Output
Mystic Pascal User Manual 61
9.4 ASSIGN (Non-Standard Feature)
ASSIGN( Filvar, String )
ASSIGN( Filvar, Standard_file )
The procedure Assign is used to associate a file variable
with a particular disk file or standard file.
The ability to assign standard files to a file variable
allows complete I/O redirection within a Pascal program. For
example, a program which creates reports could route its output
to a disk file one time and to a printer or console another time.
There is no need for separate WRITE statements for each type of
output.
10: WRITELN('Select output device for Report Listing');
WRITELN('1 = Console 2 = Printer 3 = Diskfile');
READLN(X);
CASE X OF
1 : ASSIGN( REPORTFILE, CON );
2 : ASSIGN( REPORTFILE, PRN );
3 : ASSIGN( REPORTFILE, 'REPORT.LST' );
ELSE GOTO 10
END;
Section 9: Input/Output
Mystic Pascal User Manual 62
9.5 CLOSE (Non-Standard Feature)
CLOSE( Filvar )
The Close procedure must be called after completing
processing on a disk file to ensure that the disk directory is
updated. Failure to Close a file after updating it may result in
the loss of data.
Closing a file variable to which a standard file has been
assigned is treated as a null operation.
CLOSE( F1 );
CLOSE( REPORTFILE );
CLOSE( SORTFILE2 );
Section 9: Input/Output
Mystic Pascal User Manual 63
9.6 EOF
EOF( Filvar )
Eof is a Boolean function which indicates the end-of-file
condition. Eof is true only when the file pointer points past
the last component of the file, otherwise it is false.
{ Copy F1 into F2 }
WHILE NOT EOF( F1 ) DO
BEGIN
READ( F1, X );
WRITE( F2, X )
END
Section 9: Input/Output
Mystic Pascal User Manual 64
9.7 EOLN
EOLN
EOLN( Filvar )
Eoln is a Boolean function which indicates the end-of-line
condition of a textfile. If no file variable is specified, the
function assumes the file INPUT. It is a compiler error if the
file variable is not a textfile.
{ Average N numbers from the console }
SUM := 0; N := 0;
WHILE NOT EOLN DO
BEGIN
READ( X );
SUM := SUM + X;
N := N + 1
END
WRITELN( 'The average is', SUM DIV N );
Section 9: Input/Output
Mystic Pascal User Manual 65
9.8 GET, PUT and Buffer Variables ** 1.6 **
Standard Pascal supports Input/Output operations which are
more primitive than Read and Write. In fact Read and Write are
defined in terms of the procedures Get and Put, which only move
data between a file and its buffer variable.
A buffer variable is associated with each file. Its data
type is the same as the components of the file. A buffer
variable is accessed by using the file variable's name followed
by an uparrow.
WRITE( F, X ) is equivalent to F^ := X; PUT( F )
READ( F, X ) is equivalent to GET( F ); X := F^
GET( Filvar )
The Get procedure advances the file pointer to the next
component of the file. The current component is available in the
file's buffer variable.
PUT( Filvar )
The Put procedure appends the value in the buffer variable
to the file. The condition EOF( Filvar ) must be true when Put
is called.
Section 9: Input/Output
Mystic Pascal User Manual 66
9.9 IORESULT
IORESULT
This integer function gives the return code from the last
Input/Output operation. It should be checked after each RESET
and REWRITE to be sure that the operation completed successfully.
The IORESULT values are the same values returned by DOS.
0 Successful completion
1 Invalid function number
2 File not found
3 Path not found
4 Too many open files (no handles left)
5 Access denied
6 Invalid handle
7 Memory control blocks destroyed
8 Insufficient memory
9 Invalid memory block address
10 Invalid environment
11 Invalid format
12 Invalid access code
13 Invalid data
14 (not used)
15 Invalid drive was specified
16 Attempted to remove the current directory
17 Not same device
18 No more files
Section 9: Input/Output
Mystic Pascal User Manual 67
9.10 PAGE
PAGE
PAGE( Filvar )
The Page procedure causes the textfile to begin printing on
a new page if printed on a suitable device. If no file variable
is specified, the file OUTPUT is assumed. It is a compiler error
if the file variable is not a textfile. If the file contains a
partial line of text, an implicit Writeln is issued.
Page always outputs a form feed character CHR(12).
PAGE;
PAGE( REPORTFILE );
Section 9: Input/Output
Mystic Pascal User Manual 68
9.11 READ
READ( variable_list )
READ( Filvar, variable_list )
The Read procedure is used to obtain input from a disk file
or standard file such as the console keyboard. The input
value is stored directly into one or more variables. If no file
variable is specified, the INPUT file is assumed.
READ( X, Y, Z );
READ( F1, CUSTOMER );
FOR I := 1 TO 100 DO READ( F2, X[I] );
Section 9: Input/Output
Mystic Pascal User Manual 69
9.12 READLN
READLN
READLN( variable_list )
READLN( Filvar )
READLN( Filvar, variable_list )
The Readln procedure is similar to Read but may be applied
only to textfiles. After the Readln has been processed, the file
pointer is set to the beginning of the following text line.
Unused data on the current line is skipped over.
READLN; {Skip to next line of keyboard input}
READLN( DATAFILE, PARM1, PARM2, PARM3 ); {ignore parm4,5}
Section 9: Input/Output
Mystic Pascal User Manual 70
9.13 RESET
RESET( Filvar )
The Reset procedure is used to open an existing disk file
for input or output operations. An Assign procedure must have
been used before Reset to assign a disk file name or standard
file with the file variable. Reseting a file variable to which a
standard file has been assigned is treated as a null operation.
If a disk file is not found by Reset, a run-time error
occurs.
RESET( F2 );
RESET( DATAFILE );
RESET( TEXTFILE );
Section 9: Input/Output
Mystic Pascal User Manual 71
9.14 REWRITE
REWRITE( Filvar )
The Rewrite procedure is used to create a new disk file for
output and input. If a disk file with the same file name already
exists, it is deleted before the new file is created.
An Assign procedure must have been used before Rewrite to
assign a disk file name or standard file to the file variable.
Rewriting a file variable to which a standard file has been
assigned is treated as a null operation.
If the disk directory is full, a run-time error occurs.
REWRITE( F4 );
REWRITE( REPORTFILE );
REWRITE( DATAFILE );
Section 9: Input/Output
Mystic Pascal User Manual 72
9.15 SEEK (Non-Standard Feature)
SEEK( Filvar, N )
The Seek procedure positions the file pointer at the Nth
component of the file. The first component is number 0. It is a
compiler error if the file variable is a textfile.
Seek is used for random access file processing.
SEEK( F1, INDEX );
SEEK( DOSSIER, AGENTNUM );
Section 9: Input/Output
Mystic Pascal User Manual 73
9.16 WRITE
WRITE( variable_list )
WRITE( Filvar, variable_list )
The Write procedure is used to output data values to a
textfile or non-textfile. If no file variable is specified, the
OUTPUT file is assumed. If the file is a textfile then integers,
reals and Booleans are automatically converted to text format.
WRITE('Enter longitude, latitude of target : ');
WRITE( REPORTFILE, CHR(9), 'SALES SUMMARY FOR ',MONTH );
WRITE( MODEM, SIGNON );
Section 9: Input/Output
Mystic Pascal User Manual 74
9.17 WRITELN
WRITELN
WRITELN( variable_list )
WRITELN( Filvar )
WRITELN( Filvar, variable_list )
The Writeln procedure is similar to Write but may only be
applied to textfiles. After the variables on the list have been
output, a standard end-of-line byte sequence is output. This is
(carriage_return, line_feed) 13, 10.
PROCEDURE SKIP ( X : INTEGER );
VAR I : INTEGER;
BEGIN
IF (X > 0) AND (X <= 60) THEN
FOR I := 1 TO X DO WRITELN
END;
WRITELN( F1 );
WRITELN( F1, X, Y, Z );
Section 9: Input/Output
PAS7.DOC
Mystic Pascal User Manual 75
10. Mysticin Installation Program
The installation program is used to modify the Mystic Pascal
system to match your particular computer system and program
needs. The characteristics of your video display are the major
factors to be adjusted. When Mystic Pascal starts up, it will
detect if a monochrome or color video adapter is present and
behave appropriately. If you have another type of adapter, such
as, an Enhanced Graphics Adapter, you must run the Mysticin
program before using Mystic.
To run the installation program, enter:
MYSTICIN
The program is self-explanatory and will prompt for all
required information. Various parameters determining the
configuration of storage in Mystic Pascal may also be modified.
Section 10: Mysticin Installation Program
PAS8.DOC
Mystic Pascal User Manual 76
11. Programming Notes
This section contains a list of informal programming
suggestions. Experienced programmers will find nothing new here.
Users who are new to programming may find some tips here that are
useful.
Some of these notes concern programming in general and
others are specific to Pascal.
1. Pascal procedures and functions should be kept small. If they
are 24 lines or smaller, you can view an entire procedure on one
CRT screen.
2. Give meaningful names to all the program's constants, data
types, variables, procedures and functions. Mystic Pascal allows
identifiers to be any length and all characters are significant.
When meaningful names are used, your Pascal program is self-
documenting.
3. Use the programming technique of "stepwise refinement." That
is, after you have completed the high level program design, get
some basic parts of the program running first, then gradually add
more features until the whole program is complete. If you can
see interesting results from your program early on, its good for
your morale and makes work easier. By using stepwise refinement
you can focus your attention on one small objective at a time.
Debugging is also simplified since any bugs will probably be in
the small areas most recently changed.
4. If some section of a program gradually evolves into a
patchwork of changes and changes upon changes, it is usually best
to throw it out and reprogram that section. This may seem
wasteful but you can probably reprogram some process in one fifth
the time it originally took. You will gain a cleaner, more
reliable, more efficient piece of code.
Section 11: Programming Notes
Mystic Pascal User Manual 77
5. When you have a bug in your program that takes more than 5
minutes to resolve, this simple technique may be surprisingly
effective in organizing the debugging effort.
1. Take a fresh sheet of paper -- it really
is important to have a clean work area free
from distracting unrelated information.
2. Make a list of all known symptoms of the
bug.
3. Make a list of 3 to 5 hypotheses which may
explain the error.
4. Perform further tests on the program to
gather more information. The tests should be
guided by the hypotheses.
5. Proceed with testing, adding new symptoms
to the list, deleting disqualified hypotheses
and adding new hypotheses until the answer is
found.
The purpose of this technique is to clarify your vision of
the problem state. This procedure may lead very quickly to a
solution to difficult problems. This is essentially the method
used by some types of artificial intelligence expert systems to
solve very hard problems.
Section 11: Programming Notes
Mystic Pascal User Manual 78
6. When your program creates or modifies complex data structures
it is extremely useful to have a validation procedure. The
Mystic Pascal system itself contains validation code which checks
over the structure of the Dynamic Storage and Laser at regular
intervals. This code is activated every few seconds by the IDLE
process.
Programs which create and maintain large linked lists or
trees in dynamic storage or which maintain complex tables
(arrays) of data are prone to program anomolies (bugs) which can
be very hard to detect. Since the computer is a master at the
tedious and detailed inspection of minutae, why not let it keep
an eye on your exquisitely complex structures of data?
For example, if you are creating a linked list in dynamic
storage using the NEW procedure, a validation procedure might
travel down the linked list examining each field in each record
for reasonable values. When it finds some questionable value, it
can report a probable error and perhaps interrupt the main
program.
A validation procedure may be called every time the
structure is modified or only after some major modifications. Or
in Mystic Pascal, it could be implemented as a concurrent
procedure with a rather low priority.
The small amount of time needed to write a validation
procedure for a complex data structure can be returned many times
in reduced debugging time.
Section 11: Programming Notes
PAS9.DOC
Mystic Pascal User Manual 79
A. Error Messages
Identifier Space Error -- The program being loaded has filled up
the storage area reserved for identifiers. Run the Install
program to increase the amount of Identifier Storage.
Laser Space Error -- The program being loaded has filled up the
Laser storage area. Run the Install program to increase the size
of the Laser.
Appendix A: Error Messages
Mystic Pascal User Manual 80
B. ASCII Table
00 0 NUL 2B 43 + 56 86 V
01 1 SOH 2C 44 , 57 87 W
02 2 STX 2D 45 - 58 88 X
03 3 ETX 2E 46 . 59 89 Y
04 4 EOT 2F 47 / 5A 90 Z
05 5 ENQ 30 48 0 5B 91 [
06 6 ACK 31 49 1 5C 92 \
07 7 BEL 32 50 2 5D 93 ]
08 8 BS 33 51 3 5E 94 ^
09 9 HT 34 52 4 5F 95 _
0A 10 LF 35 53 5 60 96 `
0B 11 VT 36 54 6 61 97 a
0C 12 FF 37 55 7 62 98 b
0D 13 CR 38 56 8 63 99 c
0E 14 SO 39 57 9 64 100 d
0F 15 SI 3A 58 : 65 101 e
10 16 DLE 3B 59 ; 66 102 f
11 17 DC1 3C 60 < 67 103 g
12 18 DC2 3D 61 = 68 104 h
13 19 DC3 3E 62 > 69 105 i
14 20 DC4 3F 63 ? 6A 106 j
15 21 NAK 40 64 @ 6B 107 k
16 22 SYN 41 65 A 6C 108 l
17 23 ETB 42 66 B 6D 109 m
18 24 CAN 43 67 C 6E 110 n
19 25 EM 44 68 D 6F 111 o
1A 26 SUB 45 69 E 70 112 p
1B 27 ESC 46 70 F 71 113 q
1C 28 FS 47 71 G 72 114 r
1D 29 GS 48 72 H 73 115 s
1E 30 RS 49 73 I 74 116 t
1F 31 US 4A 74 J 75 117 u
20 32 space 4B 75 K 76 118 v
21 33 ! 4C 76 L 77 119 w
22 34 " 4D 77 M 78 120 x
23 35 # 4E 78 N 79 121 y
24 36 $ 4F 79 O 7A 122 z
25 37 % 50 80 P 7B 123 {
26 38 & 51 81 Q 7C 124 |
27 39 ' 52 82 R 7D 125 }
28 40 ( 53 83 S 7E 126 ~
29 41 ) 54 84 T 7F 127 DEL
2A 42 * 55 85 U
Appendix B: ASCII Table
Mystic Pascal User Manual 81
C. ISO Standard Pascal
Mystic Pascal intends to comply 100% with the ISO Pascal
Standard Level 0. This is essentially identical to the ANSI
Pascal Standard. The British Standard Institute's official
Pascal Validation Suite is used to test compliance of Mystic
Pascal with the ISO Standard.
For several years there has been a vigorous debate over the
Pascal Standard and various non-standard compilers. The language
purists insist that every Pascal compiler comply perfectly with
the ISO Standard. The primary reason is to promote portability
of Pascal programs among the many types of computers.
On the other side are those who argue that the basic Pascal
Standard lacks many important features such as string handling,
random file access and separate compilation and therefore
extensions are necessary for all but the simplest programs.
Thankfully, the ISO Standard offers an escape from this
dilemma, although one that increases the complexity of the
compiler. A compiler may offer extensions and still be
considered standard if those extensions are documented and if
they may be switched off. This is the path that Mystic Pascal
takes.
Appendix C: ISO Standard Pascal
TUTOR.DOC
TUTOR.DOC
This file explains how to get started in Mystic Pascal and
how to run the TUTOR program.
1. Make a backup copy of the entire Mystic Pascal distribution disk.
Never use the distribution disk to run Pascal.
2. If you are using a non-standard video adapter, you must run the
MYSTICIN installation program first. The distribution version of
Mystic Pascal is setup to run on a standard IBM PC with either a
color card or monochrome card or both. MYSTICIN may also be used
to modify screen colors and video snow suppression.
3. To start Mystic, you need the files MYSTIC.EXE and MYSTIC.LIB.
Type:
MYSTIC
4. You are now in the Editor screen. Now load the TUTOR.PAS program.
Type:
F2 (Function Key 2)
L
TUTOR.PAS
5. Mystic Pascal has four screens that you can use. Type F1 to see
the Screen Selection menu.
F1 Editor
F2 Direct Mode
F3 System Display
F4 Laser Display
6. Go to the System Display screen by typing F1 to bring up the menu
and then F3 to select System Display. This screen is updated once
per second. It shows a memory map and a table of the multi-tasking
processes now running.
7. Now go back to the Editor to compile the TUTOR program. Type
F1 then F1 to reach the Editor screen.
8. To compile a program, type F2 then C. If any errors are detected
the error message will be displayed on the Editor screen and the
cursor positioned at the point the error was first detected.
9. To run the TUTOR program, go to the Direct Mode screen (F1-F2).
The backslash is the prompt character. To run a main program in
Direct Mode, just type the name of the program (as declared after
the PROGRAM reserved word).
Type:
TUTOR
10. You can work through the several lessons of TUTOR to become
more familiar with Mystic Pascal and Direct Mode programming in
particular.
11. To terminate Mystic Pascal and return to DOS, type:
F1
Ctrl-End
Directory of PC-SIG Library Disk #0965
Volume in drive A has no label
Directory of A:\
COMMENT FRM 508 2-10-86 1:03a
FILES TXT 727 8-18-87 5:00p
FILES965 TXT 2215 12-16-88 1:29p
GO BAT 38 10-19-87 3:56p
GO TXT 694 12-15-87 11:16a
MYSTIC EXE 80880 4-15-86 11:15a
MYSTIC LIB 21504 2-22-86 9:25a
MYSTICIN EXE 6000 2-03-86 4:36p
PAS1 DOC 25614 8-08-87 5:49p
PAS2 DOC 11770 2-27-86 11:50a
PAS3 DOC 7208 2-27-86 11:59a
PAS4 DOC 8441 2-27-86 12:02p
PAS5 DOC 23138 2-27-86 12:10p
PAS6 DOC 15848 2-27-86 12:17p
PAS7 DOC 1131 2-27-86 12:19p
PAS8 DOC 5554 2-27-86 12:21p
PAS9 DOC 5450 2-27-86 12:23p
PROBLEM FRM 2316 2-10-86 1:13a
READ ME 1209 3-25-86 12:45p
REGISTRN FRM 900 8-09-87 12:24p
TUTOR DOC 1935 2-05-86 11:13a
TUTOR PAS 8978 3-21-86 1:12p
22 file(s) 232058 bytes
78848 bytes free