Re: 6502 illegal opcodes questions

[pausch@saaf.se (Paul Schlyter)]

In article <nospam-467DFC.23375126052006@network-065-024-007-027.columbus.rr.com>,

> In article <e56rj1$7lo$1@merope.saaf.se>,
>  pausch@saaf.se (Paul Schlyter) wrote:
> 
>> In article <1148544621.115246.248890@y43g2000cwc.googlegroups.com>,
>> mdj <mdj.mdj@gmail.com> wrote:
> [...]
>>> The key concepts that are missing here are pointers, and more specifically,
>>> the ability to perform arbitrary arithmetic on pointer types.
>> 
>> FORTRAN, Pascal and Ada lacks this too.
> [...]
> 
> This is certainly false for Ada:
> 
> http://www.adapower.com/rm95.php
> 
> In particular, the standard package Interfaces.C.Pointers overloads the 
> "+" and "-" operators for just this purpose.
> 
> http://www.adapower.com/rm95/RM-B-3-2.html

OK, Ada has pointer arithmetic - but is it arbitrary?  Doesn't Ada impose
strict range checking for all its data structures, throwing exceptions
as soon as an attempt of out-of-range access is performed?  I though the
fundamental idea behind Ada was to provide provably secure software, and
then one cannot take pointer arithmetic as lightly as C and C++ both do.

 
> It is arguably false for many widely used flavors of Pascal including 
> Object Pascal and Turbo Pascal.
> 
> Even Fortran has a non-standard extension for this:
> 
> http://gcc.gnu.org/onlinedocs/gfortran/Cray-pointers.html

If we are going to include non-standard extensions of languages too,
then the Java camp should also include both J++ and C# .....

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