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From: Sébastien Morand on 18 Jun 2008 04:55
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> We can't help you, because you haven't shown us the code for
> SCMAL.Tools.Btrees, or even for the specified lines.
>
> Note that the ordered components of Ada.Containers have a similar data
> structure underlying them. Too bad Ada.Containers doesn't follow the Ada
> philosophy of providing basic building blocks that would make that data
> structure available.
>
> Of course, Ada compilers have to have unbounded integer and real
> packages, and the standard doesn't make them available, either.

Actually you are right I could use B-Tree or dynamic structure using
internal Ada library. But I'm still learning language and implementing a
B-Tree is a good way to learn the language and in the same time, to
review the algorithmic main topics (Stack, Queues, Linked List, Sort(s),
Base64 encoding, etc.).

Sebastien

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From: Brian Drummond on 18 Jun 2008 10:16
On Wed, 18 Jun 2008 08:41:31 +0000, S�bastien Morand
<seb.morand(a)gmail.com> wrote:

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>> The problem is here. You instantiate TestGen with Order = 1. So the upper
>> bound of Buffer is 2. Therefore the range is 1+2..Index, which should cause
>> Constraint_Error in Buffer(I).
>
>I understand, if Order = 1, then the code could never occur.
>
>Anyway, There is a test just before in the real code that avoid the
>impossible situation (index is between 1 and Order*2 always).

(Newbie qiestion, coming from VHDL, halfway through the Barnes book)

Can you not create a subtype of Positive to reflect that, and declare
both the array and index using that subtype?

- Brian

From: Sébastien Morand on 18 Jun 2008 10:32
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> (Newbie qiestion, coming from VHDL, halfway through the Barnes book)
>
> Can you not create a subtype of Positive to reflect that, and declare
> both the array and index using that subtype?

I can't create a subtype using a parameter.

generic
Order: Positive;
package Test is
-- Can't work since Order is not defined at compile time
type MyType is range 1 .. Order;
End Test;

Sebastien
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From: Ed Falis on 18 Jun 2008 10:39
Try:

generic
Order: Positive;
package Test is
subtype MyType is Positive range 1 .. Order;
End Test;

Subtype ranges based on Order are ok.
From: Dmitry A. Kazakov on 18 Jun 2008 10:42
On Wed, 18 Jun 2008 14:32:28 +0000, S�bastien Morand wrote:

>> (Newbie qiestion, coming from VHDL, halfway through the Barnes book)
>>
>> Can you not create a subtype of Positive to reflect that, and declare
>> both the array and index using that subtype?
>
> I can't create a subtype using a parameter.

No, no, you mean a *type*.

> generic
> Order: Positive;
> package Test is
> -- Can't work since Order is not defined at compile time
> type MyType is range 1 .. Order;

This would be a type. But you do can create a subtype:

subtype Index is range 1..Order; -- This is OK

Subtypes can be dynamically constrained.

--
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de
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