Member access of __gshared global object

[via Digitalmars-d-learn]

On Wednesday, 6 August 2014 at 15:18:15 UTC, Dragos Carp wrote:
> On Wednesday, 6 August 2014 at 14:36:23 UTC, Marc Schütz wrote:
>>
>> This would defeat the purpose, see the original post.
>
> sorry, I red just the last post.
>
> __gshared has no influence on this.

Indeed, it was just what the OP suspected as the culprit.

>
>> auto cmds = CONFIG.commands;
>> cmds["list"] = new Command(...);
>
> cmds is a thread local variable referencing the shared AA. But 
> if you add new elements to cmds, cmd will be reallocated and 
> the shared AA will remain unchanged. Though, updated values of 
> existing keys will be visible in the original, because no 
> relocation takes place.

This describes the semantics of regular arrays. Are you sure it 
also applies to AAs? I thought they will keep referring to the 
same data once they are initialized. But I might be mistaken...

>
> If you want to change the original you need a pointer or a 
> reference (for a setter function).
>
> auto cmds = &CONFIG.commands;
> (*cmds)["list"] = new Command(...);