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Date: Sat, 29 Oct 2011 09:29:13 +0200
From: Pascal Obry <pascal@obry.net>
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Subject: Re: Normalizing array indices
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Date: 2011-10-29T09:29:11+02:00
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Le 28/10/2011 23:13, Randy Brukardt a écrit :
> I probably would constrain the parameter to have a lower bound of 1. Using
> Ada 2012:
>
> generic
>     type Element_Type is private;
>     type Sort_Array_Type is array (Positive range<>) of Element_Type;
>     with function "<" (Left, Right: Element_Type) return Boolean is<>;
> procedure Sort(A: in out Sort_Array_Type)
>     with Pre =>  A'First 1;

Or maybe something less radical:

generic
     type Element_Type is private;
     type Sort_Array_Type is array (Positive range<>) of Element_Type;
     with function "<" (Left, Right: Element_Type) return Boolean is<>;
procedure Sort(A: in out Sort_Array_Type)
     with Pre =>  A'Last < Positive'Last - 1;

I think this covers the problem expressed by the OP, right?

Pascal.

-- 

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--| Pascal Obry                           Team-Ada Member
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