Creating programs for GEOS based PDAs and desktop computers just got easier!
Version 2.0 of IZL, an easy-to-use application development language,
is now available. Like its predecessor, the product allows rapid creation
of graphical, interactive applications directly on the GEOS platform.
Version 2.0 adds powerful new features and access to the wide variety of
hardware interfaces provided by GEOS.
IZL now comes in two flavors: a runtime environment that is distributed as
shareware, and a developer's package that allows you to create your own
applications for your GEOS desktop or PDA. The developer's version produces
binary token files (*.IZT) that can be executed by the shareware version.
The registration fee for the shareware is $20. Ordering information and
technical details about the developer's version are given below.
The shareware version contains all that you need to run IZL programs created
by the developer package, and made available as IZL token files.
The shareware package also contains four application programs written in the
IZL language, and distributed in both binary (*.IZT) and source (*.IZL)
forms. Although the shareware version is incapable of interpreting
the source files directly (it runs the binary IZT files), the source is
provided to illustrate how GEOS applications can be created quickly and
easily.
DEVELOPING IZL PROGRAMS
-----------------------
The ability to create new GEOS applications is provided by the developer's
package for IZL 2.0. To program in IZL, all that is needed is a simple
ASCII text editor, and your good ideas.
For those not familiar with IZL, a short explanation is in order.
The language contains simple statements that allow anyone to describe the look
and feel of a program's user interface in terms of the visual objects (buttons,
menu items, file selectors, etc...) that it displays, and the actions to be
performed when the user causes events (button presses, files selected) to
be triggered on the display. A user interface event like a button press
causes an associated IZL function to be executed.
An IZL function consists of a group of simple statements that are executed
sequentially, or in an order determined by control flow statements such
as IF or WHILE. Among other things, simple statements can perform I/O (GET or
PUT) with visual display objects or files, control visual display objects
(HIDE/SHOW), and assign values (numeric or string) to variables. All IZL
statements rely on the GEOS parse library to evaluate expression during the
interpretation process.
See the bundled example programs for details.
IZL 2.0 DEVELOPER'S PACKAGE
---------------------------
The above description covers the basic idea behind program development
in IZL, regardless of version. Given below is a list of new features and
enhancements over version 1.0 that are provided in the IZL developer's
package for version 2.0:
Ability to output binary token files for execution by the shareware
version of the interpreter.
Support of floating point numeric storage for variables rather
than the fixed point binary used in version 1.0.
Serial I/O on all COMM ports, including IR (COM2 on Zoomer).
An EVAL function to allow the IZL programmer access to the
parse library, so that string variables in an IZL program could
be evaluated as expressions, yielding a value to be saved in
another string variable.
Arrays of strings, version 1.0 only allowed arrays of
floating point numeric variables.
Enhanced expression handling, with expressions able to contain embedded
quotes. Strings read from text objects, files, or serial ports can also
contain quotes.
Arrays of bytes, which will allow File/Serial I/O of binary data.
Arrays of objects, allowing one section of IZL object definition code
to define a group of objects of the same type. This, coupled with the
object geometry and parental hierarchy approach provided by GEOS and IZL,
allows grids of buttons or other visual objects to be created with only a
few IZL statements.
Access to GEOS graphics primitives (DRAW, FILL, SET) that work with
the standard GEOS colors for line drawing and shape filling.
Animation via X,Y manipulation of IZL objects (MOVE statement).
File COPY, RENAME and DELETE statements.
SETDIR statement to set current directory, and built-in variable
CURDIR which contains the current directory as a string.
File selector object to allow a file to be chosen from a
directory list for the purpose of opening.
PUT sets the file filter mask, GET reads currently selected filename.
Ability to schedule events to trigger at a future time (TIMER statement).
Ability to play .WAV files on the Zoomer (PLAY statement)
New APPEND statement to output text to the end of text objects.
ORDERING INFORMATION
--------------------
When you purchase the developer's package for IZL 2.0, you will receive a
3.5 inch diskette and an IZL user's manual.
The cost of the developer's package is $56.00, plus $3.00 shipping/handling.
To order your copy, send a $59.00 check or money order to:
FERAS INFORMATION TECHNOLOGIES
315 Delaware Avenue (PA residents add 6% sales tax)
Lansdale PA 19446
Please allow 2 - 4 weeks for delivery.
NOTES:
IZL version 1.0 registered users are entitled to a 50% discount on their
purchase of the IZL 2.0 developer's package. These visionary pioneers
(you know who you are) need only send $26 ($23 + $3 s/h).
If you make use of the shareware token interpreter to run IZT files as
they become available, but have no desire to develop IZL programs yourself,
your $20 shareware registration fee will go a long way toward the creation
of more GEOS applications in the future. Please send a check or money
order to the above address.
Many thanks are extended to the IZL beta testing volunteers, with special
mention of the contributions of both Jeremy Fiebert and Doug Taylor.
Portions of this program are Copyright (c) Geoworks 1993, 1994
and used by permission.
If you have any questions regarding IZL, send E-mail to:
jferas@netaxs.com
--
John Feras Take control of your GEOS desktop or PDA
with IZL, from...
jferas@netaxs.com Feras Information Technologies