Question

[EDIT]

Thank you for your answer, my problem is the following :

Module A called Map.ml

let lst = ref [Instance1_ModuleB; Instance2_ModuleB; ...];; let is_coliding p = DoSomeWork_And_Return_A_Bool ;; .... other things here. 

Module B called Player.ml

Open Map class player_object (x_in, y_in, name_in)=  object (self)  method jump () =        if Map.is_colliding self then              DoSomeThing ();; .... 

Any clue how to make that works.

By the way, how do other programming languages hundle that? I never care about such dependency in C#!!!!! Thanks

Answer 1

If your module A only need type from module B and no value, then you can create a moduleB.mli with the interface of module B, and compile it before moduleA:

moduleA.ml:

let foo (bar : ModuleB.bar) = bar.baaz 

moduleB.mli:

class bar : object   method baaz : int   method buz : int end 

moduleB.ml

class bar = object(s)   method baaz = 3   method buz = ModuleA.foo s end 

But if you have circular dependency on value or function it there is no simple solution, as for example for :

moduleA.ml:

let li = [new bar; new bar]  let foo (bar : ModuleB.bar) = bar.baaz 

One can try to break such a circular dependency by using reference or mutable value in general:

moduleA.ml:

let li = [new bar; new bar]  let foo (bar : ModuleB.bar) = bar.baaz let _ = ModuleB.initB foo 

moduleB.ml

let foo = ref (fun x -> (failwith 'not initialized' : int))  class bar = object(s)   method baaz = 3   method buz = !foo s end  let initB f = foo := f