Re: Worker is not finished while sending message to intermediate worker

[xtreak via Digitalmars-d-learn]

On Monday, 9 February 2015 at 20:11:09 UTC, Ali Çehreli wrote:
On 02/09/2015 11:46 AM, Ali Çehreli wrote:
> threads normally start one [or] more worker threads and
> send tasks to those threads

Accordingly, the following program uses just three threads:

import std.stdio;
import std.concurrency;
import std.conv;
import core.thread;

struct Terminate
{}

void main() {

    auto square_tid = spawn(&square);

    foreach (int num; 1..100) {
        square_tid.send(num);
        auto square = receiveOnly!string();
        writeln(square);
    }

    square_tid.send(Terminate());
}

void square() {
    auto i = 0;
    bool done = false;
    auto stringWorker = spawn(&stringConverter, ownerTid);

    while (!done) {
        receive (
            (Terminate message) {
                stringWorker.send(message);
                done = true;
            },

            (int num) {
                auto square = num * num;
                writeln("sqaure : Comes in with " ,
                        num , " for " , ++i , " time");
                stringWorker.send(square);
            });
    }
}

void stringConverter(Tid destination) {
    auto i = 0;
    bool done = false;

    while (!done) {
        receive (
            (Terminate message) {
                done = true;
            },

            (int num) {
                auto stringified = num.to!string;

                writeln("string : Comes in with ",
                        num, " for " , ++i , " time");
                destination.send(stringified);
            });
    }
}

Ali

Hi Ali,

Thanks for your book :) I am using it for learning D. I want the 
stringConverter to send a message to square which in turn 
messages the main function with string "hello". So are you saying 
that message is not delivered to square from stringWorker. How 
does embedding the receive call inside the int in stackoverflow 
answer receives the message? It seems silly but how can I keep my 
threads alive to receive messages? Thanks a lot again. Please 
correct me if I am wrong anywhere.