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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.ada
Subject: Re: How can I create an empty array of a generic type?
Date: Sat, 13 Jul 2019 14:19:26 -0700
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Date: 2019-07-13T14:19:26-07:00
List-Id: <comp.lang.ada>

"J-P. Rosen" <rosen@adalog.fr> writes:
> Le 13/07/2019 à 06:11, Keith Thompson a écrit:
>> generic
>>   type Element_Type is private;
>>   type Key_Component_Type is private;
>>   with function "<" (Left, Right : Key_Component_Type) return Boolean is <>;
>>   with function "=" (Left, Right : Element_Type) return Boolean is <>;
>> package Ternary_Trees is
>>   type Key_Type is array(Positive range <>) of Key_Component_Type;
>> private
>>   Dummy: Key_Component_Type;
>>   Empty_Key  : constant Key_Type(1..0) := (others => Dummy);
>> end Ternary_Trees;
>> 
>> The Dummy value is a bit ugly. 
> You can avoid it:
>    Empty_Key  : constant Key_Type(1..0) := (others => <>);

Yes, that's better than my suggestion.  (That feature was introduced in
Ada 2005.)

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Will write code for food.
void Void(void) { Void(); } /* The recursive call of the void */