Passing Range Parameters to new instance of unbounded, boxed <> array in Ada

Passing Range Parameters to new instance of unbounded, boxed <> array in Ada

[Mace Ayres]

1) I declare - Type a_gear is array(index range <>) of Intgeger;

2) I want to create an instance of type a_gear
     Gear : a_gear (var_strt..var_end);
————————————- 
Both 1 and 2 must be declared after …. an ‘Is’ and before a ‘BEGIN’ of any code block

but I can’t code a sub program to get a user’s input for var_strt and var_end until after a BEGIN statement which too late to pass to the parameterized unbounded/Box array gear.

I am not getting the proper visibility and scope to capture user’s parameters before I declare an instance, gear, of the type a_gear, an unbounded array?

Re: Passing Range Parameters to new instance of unbounded, boxed <> array in Ada

[J-P. Rosen]

Le 14/07/2021 à 04:53, Mace Ayres a écrit :
> 1) I declare - Type a_gear is array(index range <>) of Intgeger;
> 
> 2) I want to create an instance of type a_gear
>       Gear : a_gear (var_strt..var_end);
> ————————————-
> Both 1 and 2 must be declared after …. an ‘Is’ and before a ‘BEGIN’ of any code block
> 
> but I can’t code a sub program to get a user’s input for var_strt and
> var_end until after a BEGIN statement which too late to pass to the
> parameterized unbounded/Box array gear.
> 
> I am not getting the proper visibility and scope to capture user’s
> parameters before I declare an instance, gear, of the type a_gear, an
> unbounded array?
> 
This is a classical case for a "declare" block:

procedure Your_Proc is
begin
    ... get Var_Strt and Var_End here ...

    declare
       Gear : a_gear (var_strt..var_end);
    begin
       ... use your variable here ...
    end;
end Your_Proc;

-- 
J-P. Rosen
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