Re: Interpreter for old basic programs from the line number era

On 4 Mrz., 02:07, Paul Bartlett <bartl...@[EMAIL PROTECTED]
> wrote:
> On Mon, 3 Mar 2008, thomas.mer...@[EMAIL PROTECTED]
 wrote:
> > Hello,
>
> > I wrote a basic interpreter (bas7) which can execute old basic
> > programs from the line number era (If you know GW-Basic, that
> > was the era). The interpreter is released under the GPL.
> > A description of bas7 can be found here:
>
> >http://seed7.sourceforge.net/scrshots/bas7.htm
>
> > It would be nice to get some feedback about it.
>
> I don't claim to be an expert on old BASICs, but I did look at the
> webpage, and it seems that only a subset of GW-BASIC is implemented.
GW-BASIC was not the only standard for Bas7. I searched some
archives for old BASIC programs and included some alternative
constructs from other BASICs also. You are right that only a
subset of GW-BASIC is implemented. Although the webpage says
GW-BASIC (without graphics), Bas7 contains some support for
graphics, but it is not finished. In the near future I will work
on other things, therefore I decided to introduce what I have now.
Maybe you give it a try and tell me, what features of GW-BASIC
are missing in Bas7.
> There are a lot of old perfectly good GW-BASIC programs that would not
> run under bas7.
Especially programs that contain PEEKs, POKEs, ports and other
specialties of GW-BASIC and/or DOS.
> Also, the web page stated that "spaghetti code is very
> common in BASIC."  Although it is true that a quarter of a century ago
> there were programmers who, through lack of understanding, training,
> and discipline, wrote spaghetti code, with more modern BASICs (even as
> old as Microsoft's QuickBasic and QBasic, which have been out a number
> of years, this is not necessarily so.  I have written (as have many
> people) QuickBasic programs that print out at many pages with nary a
> GOTO in them.  Fully structured.  Even GW-BASIC could be written well
> with some discipline.
I did not want to hurt your feelings. I was referring to exactly
such old BASIC programs from a quarter of a century ago.
Many of the example programs I used for testing look very
spaghetti like.

Greetings Thomas Mertes

Seed7 Homepage:  http://seed7.sourceforge.net
Seed7 - The extensible programming language: User defined statements
and operators, abstract data types, templates without special
syntax, OO with interfaces and multiple dispatch, statically typed,
interpreted or compiled, portable, runs under linux/unix/windows.