Fish 'n' More 2/fishmore-publicdomainlibraryvol.ii1991xetec.iso/fish/languages/oberon/readme

Text File | 1990-10-11 | 17KB | 515 lines

                                                       May to August 1990


                    OBERON V1.16 (Limited Version)


Introduction

This is a freely distributable demo version of a powerful compiler for a
modern, object-oriented language called Oberon.  It is the newest
development of Prof Dr Niklaus Wirth of ETH Zurich in Switzerland.  The
language is the result of a project to improve the performance and to
reduce the complexity of the language Modula-2.  Primarily, the concept of
type extension has been added to Oberon, providing object-oriented
programming facilities comparable to those of the languages Smalltalk and
C++.  At the same time, Oberon retains the notational conventions of
Modula-2 and Pascal.

The compiler on this disk has a few features seldom found in other compilers:

  - The compiler performs only a single pass, thereby providing fast
    translations.  Still, the code produced is short and fast, because the
    compiler applies carefully selected optimisations.

  - Object modules are both ALink and BLink compatible, making it possible
    to link them with modules generated by different language compilers,
    like Assembler and C.

  - Oberon programs are optimised at link time.  Unused procedures are not
    included in the executable code module.  The size of an empty program,
    for example, is less than half a kilobyte.

  - Programs are very robust at run time, because the compiler employs a
    lot of checks in order to minimise errors.  In most cases, run time
    failures do not result in a guru meditation; rather, they are captured
    by the run time system.

  - In order to permit access to the functions and resources of the Amiga
    operating system, the language has been extended by Amiga specific types.

  - There are already many library modules, and further libraries are under
    development.  They will be made available from time to time as
    additional proprietary or public domain packages.

  - Any executable Oberon program may be made resident.

  - Setting one single compiler option causes the compiler to create fully
    reentrant (pure) programs. The only restriction is, that these programs
    may not have more than 32K of global variables.


Hence, this compiler is an ideal tool to develop small and large programs
effectively.  Code re-use based on module libraries is supported via the
object-oriented features of the language, and any object previously defined
may easily be adapted to new problems.


Limitations of the demo version

This version of the compiler shall enable you to translate a few Oberon
programs and to investigate some of the compiler's features.  However, this
is not the full version.  A few restrictions have been built into the
compiler which will prevent you from using it over an extended time period.
The ideas is to encourage you to purchase the full version (see details
below) if you believe it is worth it to keep me alive.  The following
paragraphs list the restrictions build into this demo version.

  - Only a small subset of the module library and the Amiga interface
    modules are provided

  - Instructions are short and incomplete

  - Every Monday the compiler refuses to do its job

  - The source text in each module must not be longer than 10K bytes

  - The resulting object code module must not be longer than 5K bytes

  - The area for global variables per module is limited to 3K bytes

  - The area for string constants per module is limited to 1K bytes

  - For each module, the maximum number of imported modules is restriced to 6

  - The editor cannot handle more than 200 lines of source code

I realise that it is no problem for a hacker to eliminiate these
limitations.  However, any modification of the program, text and data files
is expressly forbidden.  Likewise, the possession, use and distribution of
modified versions of the included files is unlawful.  Of course, this also
applies to any copy of the full compiler version.


This disk contains the following files:

    ReadMe            The present file

    LiesMich          German documentation file

    Oberon-Report     The revised report on the language Oberon, as published
                      by ETH Zurich, Switzerland

    ModulaToOberon    The paper "From Modula to Oberon", also published by
                      ETH Zurich, Switzerland

    Install           Script file for an easy compiler installation

    Oberon            The compiler itself

    OLink             A link utility for Oberon programs, provided as a
                      comfortable alternative to BLink

    OEd               The editor

    OErr              If errors occurred during compilation, this program
                      will list the corresponding error messages

    ExeIcon           Utility similar to IconX

    BLink             The linker

    BLink.doc         Linker documentation

    Path              Path file for the compiler and for OLink

    Fehler-Meldungen  This file is used by OEd and OErr to display error
                      messages

    Demos (dir)     Demonstration programs

        Pute        CLI-based pocket calculator for INTEGER expressions like
                    103 MOD 32 * (98 DIV 3) DIV 2 - 7
        Cube        3D demonstration: cube
        Amok        3D demonstration: AMOK Logo
        Sparks      Line demonstration
        Hello       Simple hello world demonstration

    Modules (dir):  Sources of the amiga-oberon-intraface modules Exec,
                    Dos, Graphics, Intuition and the automatically
                    created definition of 'io'.

    Icons (dir)     Icons for Oberon files
                    The icons are copied by the compiler, linker etc on
                    request.

    c (dir)         Command directory, containing only MuchMore

    libs (dir)      Library directory, containing arp.library which is
                    required by the compiler etc

    sym, obj (dir)  Symbol- and object-files of the included modules. In
                    addition to the amiga interface modules, the following
                    modules are included:

                      - OberonLib:  Oberon base module, will be included
                                    in every oberon program automatically

                      - io:         standard i/o-module

                      - NoGuru:     if you import this module, error-messages
                                    will be printed in case of a run time
                                    error.

All programs on this disk, except BLink, have been written in Oberon and
translated with this Oberon compiler.


File name extension conventions

    Module / program file               .mod
    Symbol file                         .sym
    Object file                         .obj
    Object file using small data model  .objs
    Link support file (calls BLink)     .lnk
    BLink "with" file                   .wth
    Executable file                     <none>


Installation of the compiler

    The compiler may simply be installed by double-clicking the 'Install'
    icon.  The arp.library (used by OEd) is copied to logical device LIBS:,
    and this floppy disk is assigned the logical device name OBERON:.

    If you intend to run the programs from the Shell or the CLI, type the
    command

                    Path OBERON:    ADD

    after installation.


The Editor OEd

This editor supports in particular the development of Oberon programs.  It
is essentially mouse driven, and it allows you to deal with several files
at the same time.  It also provides an Oberon syntax checking mechanism.
You may start the compiler, the linker, the error message listing program
and any compiled program without leaving the editor.

Synopsis

    OEd { [-t#i] | <text file> }

You may start OEd simply by double-clicking its icon or by typing "OEd" in a
Shell or CLI window.  It is also possible to pass several text files to OEd
using multiple arguments (Shell or CLI) or multiple selection (Shift click
under Workbench).  In this case, each of the selected text files is
displayed in a separate window.  If you start OEd from a Shell or CLI window,
then you can also set the tab size explicitly (the default value is 2).  Eg
if you prefer a value of 8, type "OEd -t8 Progr.mod".  Tab size values larger
than 9 cannot be specified.  Option 'i' enforces icon generation on program
save even if OEd has been started from the Shell or CLI.

The title bar of the text window is used as a status line.  It displays
important information like error messages, cursor position, length of text,
and the file name.

Use of Keyboard

    Cursor keys (arrow keys):

    As you may have assumed already, you can move the cursor character by
    character around the text file using these keys.

    with Alt key pressed simultaneously: movement word by word / page by page

    with Shift key pressed simultaneously:  movement to beginning / end of
                                            line / text

    Backspace:  deletes character to the left of the cursor

    Del:       deletes character under the cursor
    Shift-Del: deletes whole line
    Ctrl-Del:  deletes all characters to the right of the cursor

    Return:    inserts new line at cursor position

    Tab:       jumps to the next tab stop
    Shift-Tab: jumps to the previous tab stop

    Ctrl+'S':  splits current line into two lines at current cursor position

    Ctrl+'J':  joins two lines

Use of Mouse

  Press left button to modify cursor position

  Keep left button pressed and move mouse to mark a block


The Menus

  Project Menu

    Load  (Amiga + 'L'):        load text file

    New Window (Amiga + 'W'):   open new text window

    Save (Amiga + 'S'):         save text file using current name

    Save As (Amiga + 'V'):      save text file using new name

    Save block (Amiga + 'O'):   save selected block of text

    Insert File (Amiga + 'I'):  insert text file

    Quit (Amiga + 'Q'):         exit OEd

    About (Amiga + 'J'):        display OEd information


  Search Menu

    Find (Amiga + 'F'):         find given string

    Next (Amiga + 'N'):         find next occurrence of string

    Previous (Amiga + 'P'):     find previous occurrence of string

    FindRep (Amiga + 'G'):      find and replace string

    NextRep (Amiga + 'R'):      find and replace next occurrence of string

    PrevRep (Amiga + 'H'):      find and replace previous occurrence of string

  Block Menu

    Begin (Amiga + 'B'):        mark beginning of block

    End (Amiga + 'E'):          mark end of block

    Copy (Amiag + 'Y'):         copy block

    Move (Amiga + 'M'):         move block

    Delete (Amiga + 'D'):       delete block

    TAB right (Ctrl + 'R'):     Move Block to rigtht

    TAB left (Ctrl + 'L'):      Move Block to left

    Unmark (Amiga + 'U'):       delete block marks

  Oberon Menu

    Parse (Amiga + 'A'):        check Oberon syntax - if an error is found,
                                then move to the error's position
                                parse permits finding syntax errors quickly
                                before compilation

    Compile (Amiga + 'C'):      compiles a text file which must have been
                                saved before

    Link (Amiga + 'K'):         links the compiled text using OLink

    Execute (Amiga + 'X'):      executes the linked program

    Next Error (Amiga + 'T'):   in the event of errors during compilation
                                the cursor moves to the next error position;
                                errors are listed in the status line

    First Error (Amiga + 'Z'):  moves to the first error position


The Oberon Compiler


Starting the compiler


  from the editor:

  Under the editor, the compiler may simply be started by selecting menu
  item 'compile'.


  from the CLI:

  First, the default directory must be set to the directory containing the
  text files or the 'txt' subdirectory (using CD).

  The compiler usually requires more than 4KB of stack memory. It should be
  set with the CLI command 'stack' to 10,000 to 20,000 bytes.

  Now the compiler can be started with the following command

    Oberon { [-dmsvbcrnti] <source> }

  <source> is the text to be  compiled.  The affix '.mod' may be omitted.
  If the source text is in a subdirectory named 'txt' it will be loaded
  from there.

  The options ('[-dmsvbcrnti]') refer to all the source texts that are listed
  to the right:

    Option   Effect

     '-d'    use small data-model, create reentrant (pure) code, program may
             not have more than 32K of global variables
     '-d'    use small code-model, program code may not be larger than 32K
     '-s'    disable stack control
     '-v'    disable overflow control
     '-b'    disable block control
     '-c'    disable case index control
     '-r'    disable return control
     '-n'    disable null pointer control
     '-t'    disable type control
     '-i'    produce icons

  If the compiler was started without parameters it returns with the prompt
  'in>' and expects the name of the source text.  To leave the compiler,
  press the return key.


  from the Workbench:

  If the compiler is started from the workbench, select the source texts
  using multiple selection with the mouse (press the shift key and klick
  on icons).  Then double-klick the compiler's icon.

  The compiler should not be started without parameters from the workbench,
  because in this case it will save the object and symbol files to the
  compiler's directory rather than the directory containing the source
  files.



  OLink:


  OLink simplifies the start of BLink.  From the workbench, Olink may be
  started by double clicking the icon of the object file created by the
  compiler.


  Start from the CLI:

    OLink [-bsmdi] <object file>

  <object file> is the obect file of the main module created by the compiler


  Options:

    -b   do not start BLink

    -s   start BLINK with options SMALLCODE and SMALLDATA

    -m   should be set when program was compiled using the small code-model

    -d   must be set when program was compiled using the small data-model

    -i   create icons



  OErr:


  OErr shows the errors during compilation

  Start:  OErr <source text>



  Differences to the OBERON-Report


  - Memory administration is done like in Pascal with NEW() and DISPOSE()
    and not with garbage collections.  I think that an implementation of
    the garbage collection system on the Amiga is hardly possible and that
    it would not make much sense.

  - The type guards are determined at compilation time rather than at
    loading time, as is the case on the CERES machine.


Copyright:

  This disk may be distributed freely without alternations, free of charge.

  The programs and the files on this disk may not be altered.  Altered
  versions of these programs may neither be used nor distributed.

  These programs may only be distributed together with this disk.  Ie it
  it is not permitted to copy and distribute just the editor, despite the
  fact that it is fully functional without the compiler.

  The texts by Niklaus Wirth may be distributed on their own, and eg be
  uploaded into bulletin boards.  But they may not be altered, and it
  should be ensured by an appropiate note that they will not be altered.

  BLink and BLink.doc are from the Software Distillery.  They may also be
  distributed without this disk, but only together and unaltered.

  All other files are © 1989/1990 by Fridtjof Siebert
                                     Nobileweg 67
                                     D-7000 Stuttgart 40
                                     Germany

  Any unlawful use of these files will be prosecuted.

  I will always be grateful for any information on bugs in my programs.  I
  cannot guarantee that I will find time to answer all correspondence.  So
  please direct all queries to A+L AG, and don't keep me unnecessarily from
  programming. I won't answer any questions by telephone.

  The author wil not be held liable for the correctness and functionality
  of the programs and files.  Also, the author is not liable for any damages
  incurred through the use of the programs and the files.


  Full Compiler Version

  The fully functional compiler version is expected to be released in September
  1990.  It may be ordered directly from

     A+L AG
     Im Däderiz 61
     CH-2540 Grenchen
     Switzerland

or in Australia from

     Tenera Merx Productions Pty Ltd
     Unit 1, 25 Buckingham Drive
     Wangara WA 6065

  This version will be supplied with comprehensive documentation, further
  auxiliary programs, many library modules and a complete interface to
  the Amiga's system routines (including ARP).


--- Compiler, utilities and original documentation by

    Fridtjof Siebert, Amiga Modula-2 und Oberon Klub
    Stuttgart, Reunified Germany


--- Documentation translated into Anglo-Saxon dialect by

    Rainer and Sabine Liffers, Tenera Merx Productions Pty Ltd
    Wangara, Western Australia (Down Under, also known as Banana Republic)


Thanks to Rainer and Sabine for translating this documantion. I've done some
final changes for the documentation to fit with the latest version of the
compiler. I hope I didn't include too many language mistakes...


Fridtjof.