Re: C's trikery semantic opens up backdoor in new Linux kernel

[Freejack <user@nospam.net>]

On Thu, 13 Nov 2003 16:04:02 -0500, Craig Carey wrote:

> On Wed, 12 Nov 2003 15:09:52 +0100, Vinzent 'Gadget' Hoefler wrote: ...
> 
> Ada 95 could be enhanced so that specified record fields could be
> read-only. Some one could perhaps produce data showing that it is needed
> or else it may not appear.
> 
> De-referenced pointers can identify read-only data
>   "type Ptr is access constant X;".
> Then Ada 95 lacks a limited pointer type, and also a pointer that can be
> assigned but which lacks a "=" equality operator.
 
Perhaps the introduction of a "Concatenated Type" would be helpful
here.

i.e. type Ptr is tagged access X; or some such.

The idea is thus...

	x = 2 + 3 squared
	  = 5 squared
	  = 5 * 5
	  = 25

All the functions are equivalent. Hence one could create function
pointers that are extended to point to all the functions that are
equivalent. Then one could optimize each function as long as the 
optimization does not take it out of the equality bounds.

I'm dont know if there is a way to compare Instantiations of "function
Get(X)'Class" to test for equality.

Anyways, using this method, not only would writing the to access value be
prevented, reading it outside the methods would also be unneeded.

Arg. Perhaps a little more indepth explanations is necessary.

http://www.latrobe.edu.au/philosophy/phimvt/joy/j02maf.html
http://www.latrobe.edu.au/philosophy/phimvt/joy/j04alg.html

Please ignore the atrocious syntax of that language. I find the concepts
though to be very interesting. I would not care to go whole hog with it,
but some of it might be useful.

Freejack