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digitalmars.D.learn - Share array element between threads

reply "Misu" <misugi-pwnu live.fr> writes:
Hi,

when I execute this code I have 7 7 7 as result, I think I 
understand why.

How can I execute a special task for one element ?

import std.stdio;
import std.parallelism;

void main(string[] args)
{
	class Account
	{
		public this(int id) { this.id = id; }
		int id;
	}

	Account[] accounts = [new Account(5), new Account(6), new 
Account(7)];

	foreach(acc; accounts)
	{
		task(() { writeln(acc.id); }).executeInNewThread();
	}
	
	readln();
}
Nov 06 2014
next sibling parent "bearophile" <bearophileHUGS lycos.com> writes:
Misu:


 void main(string[] args)
 {
 	class Account
 	{
 		public this(int id) { this.id = id; }
 		int id;
 	}
 ...


This is not an answer to your question, but note:

void main() {
     class Foo {}
     static class Bar {}
     pragma(msg, __traits(classInstanceSize, Foo));
     pragma(msg, __traits(classInstanceSize, Bar));
}

Output:

12u
8u

Bye,
bearophile
Nov 06 2014
prev sibling parent reply "Marc =?UTF-8?B?U2Now7x0eiI=?= <schuetzm gmx.net> writes:
On Thursday, 6 November 2014 at 10:53:32 UTC, Misu wrote:

 Hi,

 when I execute this code I have 7 7 7 as result, I think I 
 understand why.

 How can I execute a special task for one element ?

 import std.stdio;
 import std.parallelism;

 void main(string[] args)
 {
 	class Account
 	{
 		public this(int id) { this.id = id; }
 		int id;
 	}

 	Account[] accounts = [new Account(5), new Account(6), new 
 Account(7)];

 	foreach(acc; accounts)
 	{
 		task(() { writeln(acc.id); }).executeInNewThread();
 	}
 	
 	readln();
 }


It's a bug: https://issues.dlang.org/show_bug.cgi?id=2043

As a workaround, you can nest the call in another lambda:

     foreach(acc; accounts)
     {
         (Account acc) {
             task(() { writeln(acc.id); }).executeInNewThread();
         } (acc);
     }
Nov 06 2014
parent "Misu" <misugi-pwnu live.fr> writes:
On Thursday, 6 November 2014 at 13:04:18 UTC, Marc Schütz wrote:

 It's a bug: https://issues.dlang.org/show_bug.cgi?id=2043

 As a workaround, you can nest the call in another lambda:

     foreach(acc; accounts)
     {
         (Account acc) {
             task(() { writeln(acc.id); }).executeInNewThread();
         } (acc);
     }


Ok that's good. thank you !
Nov 06 2014