BBS in a Box 5/BBS in a Box -Volume V (BBS in a Box) (April 1992).iso/Files/Prog/M/MacOberon.cpt/MacOberon122.sit/Beginner.Text

Oberon Text | 1990-10-18 | 5.5 KB | 99 lines | [.Ob./.Ob*]

Syntax14b.Scn.Fnt
Syntax10.Scn.Fnt
Syntax10i.Scn.Fnt
Syntax10b.Scn.Fnt
MacOberon V1.21
Copyright (C) 1990 by Institut f
r Computersysteme
Eidgen
ssische Technische Hochschule Z
ETH-Zentrum, CH-8092 Z
rich, Switzerland
MacOberon is distributed on an "as is" basis;
no fitness for any particular purpose is claimed or implied.
Permission for unlimited duplication and distribution is
herewith granted, provided that this notice is distributed
unaltered along with the Software.
<- This is the Scroll Bar
Scroll upwards by moving the mouse into the Scroll Bar next to the line
that should appear at the top of the window and clicking the mouse button.
Getting started with MacOberon
Oberon is an extensible system.  There is no difference between functions
offered by the operating system and functions added by a user which enhance
the basic system.  As a matter of fact, Oberon abandons the notion of a
Program altogether.  Atomic actions in Oberon are called Commands.
Commands are parameterless procedures which may be executed directly
from the operating system interface.  Procedures from anywhere in a module
hierarchy may be called in this way and there is no need for a "top" module
which distributes commands to other modules.  Instead, command distribution
is built into the operating system.  When a command terminates, control is
passed back to the operating system's main loop.  However, the module that
contained the last command remains loaded in the system and all of its global
variables remain unaltered.  Subsequent commands may reference these
variables freely.
The granularity of commands is quite fine.  Typical commands display the
directory of a storage device, increase the font size of the text last selected or
compile the contents of the active window.  A user may execute commands in
any sequence and may thus be working on completely different problems in
different windows at the same time.  We call this "one-process multitasking".
Using Commands
Commands are activated by the use of an Action Button (the control key on
the Macintosh).  Pressing the Action Button while pointing at any text
anywhere on the screen will try to execute a command of that name.  This
may be text in a word processor document, captions in a CAD document and
even the title of windows.
The system will then attempt to interpret the text that is pointed at as
"Modulename.Commandname" and search for the corresponding module,
possibly loading it from disk if it cannot be found in memory.  If the module is
present or can be loaded, it will then search for the requested command and
execute it.  If the module or the command cannot be found, the system will
simply resume its usual input state.
A command can determine from where it was called (menu bar, body text) by
inspecting certain global variables of the system and can access any text that
may follow the command that was invoked (parameters).  It can also access
text at the caret position and a global, time-stamped list of all text selections
which are currently active in different windows on the screen.  All of these
can also be used to extract parameters.
The main feature of Oberon is extensibility.  A user can add an arbitrary
number of commands to the system at any time simply by writing a module
and compiling.  There is no need to install the command (it may be activated
as soon as compilation is completed) and modules containing commands are
not added to the system until an actual call is made. The <working menus> of
commands that users keep (called Tools in Oberon) are regular document
processor windows containing editable texts.
Using the Mouse in MacOberon
Oberon expects a three-button mouse.  The two buttons missing on the
Macintosh are mapped onto the keyboard as follows:
  control key = Action button = MM (middle) Oberon mouse button
  option key = Select button = MR (right) Oberon mouse button
  mouse button = Position button = ML (left) Oberon mouse button
Mouse Use:
  execute command = Action
  position caret = Position
  select range = drag Select
  select to beginning of line = double click Select
  move viewer = drag Position in title bar
  reposition viewer = interclick Action during move
Scrolling (in scroll bar):
  make line next to cursor the new top line = Position
  position absolutely relative to document = Action
  scroll to top of document = Select
Shortcuts:
  copy to caret = interclick Action during Selection
  copy from selection = interclick Action during Position
  delete selection = interclick Position during Selection
  copy format to selection = interclick Selection during Position
  unload module prior to command execution
    = interclick Position during Action
  cancel = press all three buttons
Use Edit.Open to open a window onto a file.  You may specify the name
of the file you wish to open on the same line as the Edit.Open command,
or alternatively you may execute a command Edit.Open followed by an ^
arrow or a line break.  It will then take its parameters from the most recent
selection.  Selecting the first character of the file name is sufficient (press the
Option key when the mouse arrow points to it).
                                                                                    Michael Franz, 17.10.90
Edit.Open Test.Mod    {Simple example and instructions on using compiler}
Edit.Open EdT.Mod    {A simple extension of Edit}
Edit.Open TickCounter.Mod    {Oberon Tasks example}