[Oberon] RE: Where's Coco's 'hello world' ?

Chris Glur easlab at absamail.co.za
Sat Aug 2 09:03:26 MEST 2008

Jorg_Straube wrote:

> > Normally, Wirth lives according to "Make it as
> > simple as possible but not simpler".
> > 
> > Look at this syntax:
> > a) IF Cond THEN Statments END;
> > b) WHILE Cond DO Statments END;
> > 
> > Sometimes during debugging algorithms I find
> > myself in the position to start with an IF and
> > change it later to a WHILE! (Don't know, if
> > I'm the only one with such an approach...)
> > 
> > So, I have to change the "IF" into a "WHILE"
> > 
> > I always was wondering why he did not propose
> > this syntax:
> > a) IF Cond DO Statements END;

Chris Burrows wrote:
> Wirth has actually made a move in a similar direction very recently. In
> Oberon-07 he has introduced an extension to the WHILE statement which has a
> DO following an ELSIF.
>   WHILE expression DO statementSequence

This was all thrashed-out in the '60 by Wirth & other high-priests for Algol ?
Of course there are marginal considerations, eg. if "FOR" should be included.

John Drake wrote:
> Coco.Report.ps is an Adobe Postscript file.  There is a free Postscript viewer for Linux
> called Ghostscript.  You can find a more detailed user manual in PDF format here:
> http://www.ssw.uni-linz.ac.at/coco/

Thanks, the *.ps which eventually did render via gv is from Linz.
It's "PS-Adobe-3.0".
I'm guessing that "PS-Adobe-2.0" 'time', linux's gv was immature,
and the newer version can't handle "PS-Adobe-2.0".

Aubrey.McIntosh wrote:
> I actually use Coco in lots of projects.  Recently, I modified the
> grammar given in the N. Wirth papers and have a Coco .atg file for
> PICL that will compile with no Coco errors.

Did you still keep his proposed forth-like syntax for the bit-operations ?
Is Wirth's  *.atg file available/public-domain ?
Have you done testing down to the hardware level ?
I've got a set of hardware tests that I designed for the Picforth compiler,
which found a bug, which the author quickly fixed - years ago.

Since you have experience with coco, can't you just write the
'hello world' for eg. my task, or your idea of a 'hello world'.
I'll fill in the procedure-actions if you give them descriptive IDs.

I don't want to work-blind, by just running a *.atg without
knowing the background.  
My query to the <pic compiler> mailing list 'if pic16c84
is still available', got repeated condemnation for not using 
the later, better, cheaper version  -- altho' pic16c84 is 
still available.
The point is:
* hardware is cheap,
* software is expensive,
* your OWN knowledge is the most valuable.
That's why/how M$ was able to flourish: not forcing the
original DOS users to abandon their invested labour ?


== Chris Glur.

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