Re: PAR (Was: Embedded languages based on early Ada)

Dmitry A. Kazakov a écrit :

Why is it bad programming? Consider this:

declare
Sum : Numeric := 0.0;
begin in parallel
Sum := Sum + Integrate (Series (1..N);
Sum := Sum + Integrate (Series (N+1..2*N);
Sum := Sum + Integrate (Series (2*N+1..3*N);
...
end;

task type Integrate is
entry Run (Series : in Series_Type);
entry Result (Value : in out Numeric);
end Integrate;

Max : constant := 30;
T : array (1 .. Max) of Integrate;

declare
Sum : Numeric := 0.0;
S : Numeric;
begin
for K in T'Range loop
T (K).Start (Series ((K-1) * N + 1 .. K * N));
end loop;

for K in S'Range loop
T (K).Result (S);
Sum := Sum + S;
end loop;
end;

Typed directly from my mail client, sorry if it is not compiling :)

I don't see the point of PAR which create dynamically threads all the
time. A waste of time! The T tasks above can be reused during all the
application lifetime if necessary.

Pascal.

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