Re: Random number generation

[Georg Bauhaus <rm.dash-bauhaus@futureapps.de>]

On 30.12.10 13:25, Mart van de Wege wrote:
> Georg Bauhaus <rm.dash-bauhaus@futureapps.de> writes:
>>
>> OTOH, the Size parameter is fixed at 6, so subtype Die_Size and
>> the generator could be placed outside Roll.  Anyway, another
>> nest will give suitable life times to the objects involved.
>>
> How does that work?

Using another level of nesting to control life time
and parameterization:

procedure Rolltest is

    procedure Setup_And_Roll (Size: Positive) is

        subtype Die_Size is Positive range 2..Size;
        package Die is new Ada.Numerics.Discrete_Random( Die_Size );
        G : Die.Generator;

        function Roll ( Number : in Positive;
                        Modifier : in Integer := 0 ) return Integer is
            Result : Integer;
            Temp : Integer;
        begin
            Result := 0;
            for I in 1..Number loop
                Temp := Die.Random(G);
                Result := Result + Temp;
            end loop;
            Result := Result + Modifier;
            return Result;
        end Roll;

    begin
        Die.Reset(G);
        for I in 1..10 loop
            Put(Roll( Number => 3 ));
        end loop;
    end Setup_And_Roll;

begin
    Setup_And_Roll (Size => 6);
end Rolltest;