00:47 <wobba> Hello, is this the place to ask possibly stupid questions?

06:48 <vaninwagen> wobba given there are no stupid questions, go straight ahead and ask. We'll do our best to answer

06:51 <vaninwagen> drakode thats a kinda broad question. You can do anything you need with Pony. But the most compelling use case for pony would be if you have a hard concurrency problem at hand. Or some networking code, think a game backend server or a webserver. Think of wallaroo, a stream processing engine, all those things that need high concurrency and low latency

06:51 <vaninwagen> There are probably a lot more use cases, i just named a few examples

06:51 <vaninwagen> If you gotta do something like this but do it safely

20:13 <ein_> hello~

20:13 <ein_> i have a question about the c-ffi

20:14 <ein_> specifically, one of the ffi-functions i want to wrap requires an array to be allocated, the pointer to it passed, and the function will populate the array with values

20:14 <ein_> now, the .cpointer() method on Array seems to return a tag

20:15 <ein_> so i'm wondering if that'd be a suitable way to pass the underlying memory-block to the c-function?

20:16 <ein_> i also looked at the FFI-example, and there the array is is just passed in as is, but that would pass the pointer to the struct of the array instead right?

20:16 <vaninwagen> Array.cpointer() is exactly the right way

20:16 <ein_> okay

20:17 <ein_> thank you (y)

20:17 <vaninwagen> The reference capability is erased at runtime

20:17 <vaninwagen> It just gives you another safety layer for accessing memory blocks in pony

20:17 <vaninwagen> You cant do much with such a pointer, because it might be unsafe to fiddle with it

20:17 <ein_> ye, i wasn't worrying that the C lib would have issues, just if it being a tag meant that it was bad form, or that pony maybe expects some things which would be invalidated

20:17 <vaninwagen> But if you cross the bordee to c ffi land, there be dragons anyway :)

20:18 <ein_> true

20:18 <ein_> thanks a bunch

20:18 <ein_> will come back and complain if computer catches fire tho

20:18 <ein_> xp

20:18 <vaninwagen> sure!

20:28 <ein_> actually i have another question:

20:29 <ein_> as said, i'm wrapping some C-stuff, and if i have a struct for which i don't need to have access to the fields

20:30 <ein_> can i declare the c-functions to return a primitive, associate functions with that primitive, and use "this" to pass the actual struct value along to the c-ffi calls?

20:30 <ein_> or would i need to wrap the primitive in a class?

20:40 <vaninwagen> I do not fully understand your approach but i think it wont work that way

20:41 <vaninwagen> A pony primitive cant have fields and such

20:42 <vaninwagen> And i dont know all the details how the pony runtime handles the memory for primitives, but you most likely run into issues

20:42 <vaninwagen> Id suggest stick to a Pointer or use a struct

20:42 <vaninwagen> Which you could both wrap with a class

20:44 <vaninwagen> Or are you talking about numeric primitives like U32 ?

20:47 <ein_> no, i have a c-struct which has some fields

20:47 <ein_> but i don't require access or knowledge about the fields

20:47 <ein_> i just thread them along to functions etc.

20:48 <ein_> i've just converted what i had wrapped to just be a primitive, and declared the c-stubs to return such a primitive

20:48 <ein_> and it seems to work fine

20:53 <ein_> here's a gist for the pony source: https://gist.github.com/spreadLink/dc9a5541df73aa289ab6ca5373dfa601

20:53 <ein_> and here the relevant c-lib https://bitbucket.org/libtcod/libtcod/src/ea46403d558c89afa632cb02b49b2b815accdcf6/include/color.h?at=default&fileviewer=file-view-default

20:53 <ein_> header i mean

20:56 <ein_> for what it's worth, the tutorial also mentions to use primitives to represent struct-pointers

20:56 <ein_> i do wonder, tho, how it all behaves with garbage-collection etc.