Re: Generic Zero Length Array

["Egil Høvik" <egilhovik@hotmail.com>]

On Feb 22, 2:31 pm, shaunpatter...@gmail.com wrote:
> I have a bit of legacy code in my system that I am trying to remove
> all warnings from.
>
> The package is a generic -- with:
>
> type Element is (<>);
> type Element_List is array (Indexing range <>) of Element;
>
> I have been stumped by one compiler warning where one of the functions
> needs to return a zero-length empty generic array:
>
> warning: variable Result_String is read but never assigned
>
> code:
>
> if Error_Condition then
>   declare
>     type Result is new Element_List (Indexing.First + 1 ..
> Indexing'First);
>     Result_String : Result;
>   begin
>      return Element_List (Result);
>   end;
> end if;
>
> How do I initialize this array when I can't know what type it is or
> will be?
>
> Thanks
>
> --
> Shaun


A new generic parameter Null_Element would do the trick, but
that means changing code wherever the generic is used...

type Element is (<>);
type Element_List is array (Indexing range <>) of Element;
Null_Element : Element;


then you could rewrite the above code to

if Error_Condition then
  return Element_List'(Indexing'First..Indexing'First-1 =>
Null_Element);
end if;


--
~egilhh