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From: Stephen Leake <stephen_leake@stephe-leake.org>
Newsgroups: comp.lang.ada
Subject: Re: Generalized Loop Iteration and User-Defined Indexing with more than two parameters.
Date: Sat, 07 Nov 2020 15:54:14 -0800
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"Randy Brukardt" <randy@rrsoftware.com> writes:

> "Blady" <p.p11@orange.fr> wrote in message 
> news:ro3qms$1vdh$1@gioia.aioe.org...
>
>> 2) In Ada.Iterator_Interfaces, why Has_Element is a generic formal 
>> parameter instead of an abstract function of Forward_Iterator interface?
>> As:
>>    function Has_Element
>>      (Object   : Forward_Iterator;
>>       Position : Cursor) return Boolean is abstract;
>> The current way requires that Cursor type has the container reference 
>> embedded and cannot be a simple index type.
>
> I suppose other designs could have been chosen. 

In addition, you can store the container reference in your Iterator object.


-- 
-- Stephe

Written from unceded ancestral homelands of the Huichiun, an Ohlone
people,for which I pay Shuumi Land Tax