OpenEuphoria

RE: 'Unknown' and three-valued logic (was: Example where Euphoria ...)

• Posted by rforno at tutopia.com Nov 25, 2002
• 537 views

What you say about C is totally right. C does not check for pointers to
unexisting addresses, or addresses with random data; does not check for
uninitialized variables; does not verify validity of subindexes; does not
check for overflow; and has maybe some other flaws I am not recalling just
now.
But keep in mind that C was designed (not explicitly) as a replacement for
Assembly language, with the proviso that it can run under different
architectures.
Being an Assembly substitute, it has no place for nil data, the same as
Assembly. Machines work according to Boolean logic, which neither has place
for nil, only for True or False, or what is the same, 1 or 0.
The Euphoria language is another issue, and surely could have been designed
to work with some data type called "nil", but it has not. So, the only
solution I see to the problem is designing a package for it. But as I said
in a previous post, usual programming tasks do not need this facility, and
moreover, it is a pain in the neck to deal with tri-valued logic, as some
data bases allow.
Best wishes.
----- Original Message -----
From: Rom <kjehas at frisurf.no>
To: EUforum <EUforum at topica.com>
Sent: Sunday, November 24, 2002 3:30 PM
Subject: Re: 'Unknown' and three-valued logic (was: Example where Euphoria
...)



It is all C's fault.

I remember my first Toolswork C-compiler. It was absolutely a disasterous
experience for someone who's only experience was with Basic interpreters.
First the syntax errors.... then, if the program was not right, looose
pointers and that kind of things, causeing the program to go beserk and
easily crashed whole computer.

I am wondering how much C has shaped other programming languages, too? When
other languages are created using C, then the "*" operator are most likely
to be a C call? And the same goes for the relational operators (  =,>...) so
that the other languages created with C are likely to inherit the same
weaknesses as C? And C does not reserve any flag for a variable being
instanciated or not, it just uses whatever it find at that memory address,
there is no checking about the variable has been set or not (that is very
speedy ... which the designers of C wanted it to be).

So basicly, it the program is not right, then output will be rubbish
values... not nil values. When you tell a C program to multiply to variables
that are not set, then the result is rubbish... and there is no obvious way
to test if the values are rubbish or not.

When C evaluates a conditional statements upon a boolean value .... that is
not set ... then C branches in the wrong direction ...(and there is no
obvious way to test if current branch is caused by rubbish branchin)...
instead of branching in the direction it should have gone when branching is
unsolved.

It could all have been different... if there had been a nil flag for all
variables .. then all the compilers created with C would also have been
different ... because if C had been different, then the other compilers
would have inherited a lot of that behavior ... the best of it, hopefully?

It is all C's fault, behaving like an idiot.

Regards
Rom

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