Re: [Etoile-dev] Re: Io language for StepTalk on Cocoa

[Quentin Mathé]

Le 26 mai 06 à 09:56, Stefan Urbanek a écrit :

> Citát Quentin Mathé <gnustep-quentin@club-internet.fr>:
>
> > Le 25 mai 06 ŕ 12:03, Nicolas Roard a écrit :
> >
> > > Really cool ! io_objc works fine on gnustep. Impressive !
> > > in StepTalk it seems to be broken though (seems a problem not saving
> > > the context)
> >
> > Good news, I can give up on my buggy old version :-).
> >
> > It works very well. Excellent work ! I got it working with StepTalk
> > (GNUstep) properly yesterday. I hacked IoLanguageEngine to have
> > Io_State kept value in an ivar. This way between each call to -
> > interpretScript:inContext: the context is maintained. The correct way
> > to do it would be to store Io_State in STContext instance I think.
>
> How it works? Do you need some language-engine specific  
> configuration to be
> saved into the STContext in a special way (different to context's  
> variables)?

We only need to store Io_State, it's a C structure, we may probably  
just wrap it in an NSValue object part of STContext variables  
dictionary.
For STContext, it could be better to provide an instance variable  
which is just a hash table where language engine states are keyed by  
language engine instances. That would allow :
- to pass a context accross language engines, without polluting  
STContext variables dictionary
- to handle different execution contexts on language engine side  
without having to set up a new language engine instance.
Finally well, it would be mandatory if it's not possible to wrap  
Io_State in NSValue.

> If yes, would it be thread safe - when two threads will be acessing  
> the same
> (parent)context?

I don't really know. I think it's should be possible to have it  
thread safe. It would be by running method calls as asynchronous  
messages on Io runtime side.

> Btw. how it is with bridging Objective-C objects with io? Is it  
> only isolated io
> computation engine or can I pass objects in and out?

At this time, it's an isolated Io engine. It should be possible  
easily to pass objects in and out since Io_State references the Lobby  
(list of root objects in Io execution context). This could be  
accomplished by calling C functions that set/update slots in Lobby.

> Is it possible to implement STEngine createMethod:... for the io  
> language?

I think so. A method is an object in Io. Moreover any objects in Io  
is just a key/value pairs list, each key/value pair is called a slot.

> > As a side note, I have been unable to load AppKit environment with
> > StepTalk, either stexec or stshell (using the flag -env AppKit).
>
> What error are you getting?

I have to check on my GNUstep install. I don't remember right now.

Quentin.

--
Quentin Mathé
qmathe@club-internet.fr