07:45 <ulfdoz> When I allocate a custom block via alloc_custom, do I still need to register it with the gc, or is it already registered?

07:46 <zmdkrbou> you don't need more

07:51 <dylan> But do remember to use CAMLparam and CAMLreturn with it. :)

07:52 <dylan> (or, rather, whatever C-level variable that eventually contains it)

07:56 <ulfdoz> C-Code looks quite good until now, but there are still ~80% of it todo.

07:57 <ulfdoz> The things with side effects in ML-structures caused in C-World belong to them. :(

08:54 <ulfdoz> Is there a clean way to convert an value with an type 'a (polymorphic in ml) to a void pointer, which then can be safely accessed in c-world, so that there is a valid value at the target of the void pointer? Unfortunately there is no way to predict, what the void pointer is casted to.

09:01 <ulfdoz> to illustrate it: in C - struct foo { void *bar } is represented in ocaml as type 'a foo { bar : 'a};; Now I need some translation for ml's foo.bar to C's foo->bar.

09:20 <fluxx> I just represent C structs as 'type foo'

09:20 <fluxx> so only C-code can construct or access them

09:21 <fluxx> but I guess this is not what you're after?

09:21 <fluxx> I suppose the type could just as well be 'a foo :)

09:21 <fluxx> and then val get_foo : 'a foo -> 'a

11:27 <ulfdoz> fluxx: No it is data to exchange between the library and the programm. E.g. it could be a supplied username or a hash of a password. It can be necessary to modify this in the app.

11:28 <ulfdoz> But currently gcc complains about caml__frame not being declared, and indeed, I can't find any declaration. It seems to be used by CAMLreturn.

11:43 <ulfdoz> Hah! compiles. actually I haven't uses CAMLparamN, which seems necessary.

16:23 <ulfdoz> Can I tag a string after creation, to have ml and c refering to the physically same string?

16:24 <ulfdoz> Basically, this would mean, to declare the C-string an ocaml-block.

16:27 <ulfdoz> Evil voices tell me something like str = (value *) caml_alloc(string_length(c_str), String_tag); Store_field(str, 0, c_str);

16:28 <ulfdoz> err, s/string_length(c_str)/sizeof(char *)/