sslot 0.3 release

[Lutger]

Lutger wrote:
> Dejan Lekic wrote:
>> Lutger, my suggestion is to do what QT does - 
>> http://doc.trolltech.com/4.2/threads.html#signals-and-slots-across-threads 
>>
>>
>> Kind regards
>>
>> PS. I would like to see this in Phobos' signal/slot implementation.
> 
> Thank you for the link. It is still not clear to me what is necessary, 
> the QT s/s mechanism is tightly integrated to the whole framework so not 
> seems to be applicable.
> 
> What it comes down to looks like a lot of mutexes to me though. I am not 
> so familiar with multi-threaded programming, perhaps you can help me 
> with these questions:
> 
> Would it be preferable to have a thread safety as an option, and if so 
> in what way? Versioning or seperate classes?
> 
> Do reads from (non-volatile) data need to be synchronized?

I found the answers to my own questions, but upon reflection there seems 
to be a lot of potential for deadlocks. It will probably take a while 
for me to figure out the details, I don't want to infest sslot with 
subtle bugs.