Re: Need Help On Ada95 Problem

[Shark8 <onewingedshark@gmail.com>]

On Feb 9, 11:32 pm, "Alex" <a...@foo.invalid> wrote:
> Sure you can just use 'Pos! While the positions of the digit characters
> do not correspond directly to their values, they are sequential in the
> ASCII mapping, so all you have to do is subtract the position of the
> Character '0' from each one to calculate its value. Check it out:
>

I know that, I've done it before; I think you misunderstood what I was
trying to say here (or perhaps I was simply using the wrong language):

>
> Shark8 wrote:
> > You can't just index into Character (via 'POS, 'VAL and index-
> > manipulation) because the mapping isn't sequential;
> > or even partly-sequential in the ASCII codes.
>
> > See the (3,4,5) association with (V,A,L) and (6,7,8) with (T,I,N).

Do, let me rephrase:
Letting F(I) be the function taking an integer and returning the
correct character we see that F(3) = V, F(4) = A, and F(5) = L;
this means that the internals of F cannot be a simple offset indexing
into ASCII. Furthermore, as F(6) = T, F(7) = I, and F(8) = N we see
that there is no intuitively obvious subcycle such as one sees when
numbering a chessboard (the multiplication/mod relationship).

Therefore, using a mathematical (arithmetic) function to relate these
numbers and the associated ASCII codes is likely inappropriate.