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From: "Jeffrey R. Carter" <spam.jrcarter.not@spam.not.acm.org>
Newsgroups: comp.lang.ada
Subject: Re: How to access Vector.Index_Type?
Date: Mon, 18 Mar 2019 20:35:32 +0100
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Date: 2019-03-18T20:35:32+01:00
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On 3/17/19 9:43 PM, jakub.dabek@gmail.com wrote:
> I have the following program
> 
>      with Ada.Containers.Vectors;
> 
>      procedure Test is
>          package MyVec is new Ada.Containers.Vectors(Natural, Natural);
>          Var : MyVec.Index_Type;
>      begin
>          null;
>      end;
> 
> I get the following error:
> "Index_Type" is not a visible entity of "MyVec"
> 
> How can I access the index type (`Element_Type` gives the same error message), without just writing `Natural`?

This is refreshing. Usually people complain that Ada makes them type too much. 
It's unusual to see someone complain that Ada makes them type less than they want.

If you are dealing with pkg Myvec, Ada presumes that you will look at the 
instantiation and see that it says

Index_Type => Natural

and use Natural when you want an index.

-- 
Jeff Carter
"What I wouldn't give for a large sock with horse manure in it."
Annie Hall
42