Collection of Tools & Utilities/Collection of Tools and Utilities.iso/ada/adatu200.zip/ADA_TUTR.ADA

Text File | 1991-03-25 | 26KB | 518 lines

-- ADA_TUTR.ADA   Ver. 2.00   25-MAR-1991   Copyright 1988-1991 John J. Herro
-- Software Innovations Technology
-- 1083 Mandarin Drive NE, Palm Bay, FL  32905-4706   [phone]
--
-- Before compiling this file, you must compile ONE of the following:
--
--    MERIDIAN.ADA  Recommended when using a PC with a Meridian Ada compiler
--                     and the Meridian DOS Environment Library.
--    UNIX.ADA      Recommended for UNIX based systems, if you can also
--                     compile ONECHAR.C or ALTCHAR.C with a C compiler and
--                     link with Ada.
--    VAX.ADA       Recommended when using VAX Ada.
--    VANILLA.ADA   "Plain vanilla" version for all other systems.  Should work
--                     with ANY standard Ada compiler.  On some systems,
--                     VANILLA.ADA may require you to strike ENTER after each
--                     response.  However, you don't have to strike ENTER with
--                     recent versions of TeleGen Ada by Telesoft.
--
-- See the PRINT.ME file for more information on installing ADA-TUTR on other
-- computers.
--
--
-- Before Running ADA-TUTR on a PC:
--
-- ADA-TUTR uses ANSI escape sequences for highlighting, cursor positioning,
-- reverse video, etc.  Before ADA-TUTR will work correctly on a PC, you must
-- install the device driver ANSI.SYS, which came with your copu of DOS.  To
-- install ANSI.SYS, do the following:
--
-- 1.  If there's a file CONFIG.SYS in the root directory of the disk from
--     which you boot, type it and look for a line saying "DEVICE=ANSI.SYS"
--     (without the quotes), in either upper or lower case.  If that line isn't
--     present, add it to CONFIG.SYS anywhere in the file, using an ordinary
--     text editor or word processor in the non-document mode.  If there's no
--     CONFIG.SYS file, create one containing the single line "DEVICE=ANSI.SYS"
--     (without the quotes).
--
-- 2.  If there's no file ANSI.SYS in your root directory, copy ANSI.SYS from
--     your DOS distribution diskette to the root directory of the disk from
--     which you boot.
--
-- 3.  Reboot the computer.  ADA-TUTR should then work correctly.
--

-- Introduction:
--
-- ADA-TUTR provides interactive instruction in the Ada programming language,
-- allowing you to learn at your own pace.  On a PC, access to an Ada compiler
-- is helpful, but not required.  You can exit this program at any time by
-- striking X, and later resume the session exactly where you left off.  If you
-- have a color monitor, you can set the foreground, background, and border
-- colors at any time by typing S.
--
-- ADA-TUTR presents a screenful of information at a time.  Screens are read
-- in 64-byte blocks from the random access file ADA_TUTR.DAT, using DIRECT_IO.
-- For most screens, ADA-TUTR waits for you to strike one character to
-- determine which screen to show next.  Screens are numbered starting with
-- 101; each screen has a three-digit number.  Screens 101 through 108 have
-- special uses, as follows:
--
-- 101 - This screen is presented when you complete the Ada course.  It
--       contains a congratulatory message.  After this screen is shown,
--       control returns directly to the operating system; the program doesn't
--       wait for you to strike a character.
-- 102 - This screen is presented when you exit ADA-TUTR before completing the
--       course.  After this screen is shown, control returns directly to the
--       operating system; the program doesn't wait for you to strike a
--       character.
-- 103 - This screen is shown whenever you strike X.  It displays the number of
--       the last screen shown and the approximate percentage through the
--       course.  It then asks if you want to exit the program.  If you strike
--       Y, screen 102 is shown and control returns to the operating system.
--       If you type N, screen 108 is shown to provide a menu of further
--       choices.  From screen 103, you can also strike M to see the main menu
--       (screen 106).
-- 104 - This is the opening screen.  It asks if you've used ADA-TUTR before.
--       If you strike N, a welcome screen is presented and the course begins.
--       If you strike Y, screen 107 is shown.
-- 105 - This screen allows you to type the number of the next screen you want
--       to see.  For this screen, instead of striking one character, you type
--       a three-digit number and presses ENTER.  Any number from 104 through
--       the largest screen number is accepted.
-- 106 - This screen contains the main menu of topics covered in ADA-TUTR.
--       When you select a main topic, an appropriate sub-menu is shown.
-- 107 - This screen is shown when you say that you've used ADA-TUTR before.
--       It says "Welcome back!" and provides a menu that lets you resume where
--       you left off, go back to the last question or Outside Assignment, go
--       to the main menu (screen 106), or go to any specified screen number
--       (via screen 105).
-- 108 - This screen is shown when you answer N to screen 103.  It provides a
--       menu similar to screen 107, except that the first choice takes you
--       back to the screen shown before you saw 103.  For example, if you
--       strike X while viewing screen 300, you'll see screen 103.  If you then
--       answer N, you'll see screen 108.  From 108 the first menu selection
--       takes you back to 300.
--

-- Format of the Data File:
--
-- ADA-TUTR.DAT is a random access file of 64-byte blocks.  The format of this
-- file changed considerably with version 2.00 of ADA-TUTR.  It's now much more
-- compact, and, although it's still a data file, it now contains only the 95
-- printable ASCII characters.
--
-- The first block of ADA_TUTR.DAT is referred to as block 1, and the first 31
-- blocks together are called the index.  Bytes 2 through 4 of block 1 contain,
-- in ASCII, the number of the welcome screen that's shown when you say that
-- you haven't used ADA-TUTR before.  Bytes 6 through 8 of block 1 contain the
-- number of the highest screen in the course.  (Bytes 1 and 5 of block 1
-- contain spaces.)
--
-- Bytes 9 of block 1 through the end of block 31 contain four bytes of
-- information for each of the possible screens 101 through 594.  For example,
-- information for screen 101 is stored in bytes 9 through 12 of block 1, the
-- next four bytes are for screen 102, etc.  For screens that don't exist, all
-- four bytes contain spaces.
--
-- The first of the four bytes is A if the corresponding screen introduces an
-- Outside Assignment, Q if the screen asks a question, or a space otherwise.
-- The next two bytes give the number of the block where data for the screen
-- begins, in base 95!  A space represents 0, ! represents 1, " represents 2,
-- # represents 3, $ represents 4, etc., through all the printable characters
-- of the ASCII set.  A tilde (~) represents 94.
--
-- The last of the four bytes gives the position, 1 through 64, within the
-- block where the data for this screen starts.  Again, ! represents 1,
-- " represents 2, # represents 3, etc.
--
-- Data for the screens are stored starting in position 1 of block 32.  In the
-- screen data, the following characters have special meaning:
--
--           %  turns on high intensity.
--           @  displays the number of spaces indicated by the next
--                 character (# represents 3, $ represents 4, etc.)
--           \  turns on reverse video and leaves one space.
--           ^  turns on high intensity and leaves one space.
--           `  restores normal video.
--           {  causes CR-LF.
--           }  moves cursor to row 24, column 1, for a prompt.
--           ~  restores normal video and leaves one space.
--
-- These characters have special meaning in screen 103 only:
--
--           #  shows approximate percentage through the course.
--           $  shows the number of the screen seen before 103.
--
-- Immediately after }, b represents "Please type a space to go on, or B to go
-- bac