module type Container = 
sig
	type 'a t
	exception Empty of string
	exception Full of string
	
	val create: unit -> 'a t
	val put: 'a * 'a t -> unit
	val take: 'a t -> 'a
end;;

module ContainerOption =
struct
		type 'a t = { mutable a : 'a option }
		exception Empty of string
		exception Full of string
		
		let create() = { a = None }
		
		let put (e, c) = 
			match c.a with
			| None -> (c.a <- Some e)
			| _ -> raise(Full "f")
		
	  let take c = 
			match c.a with
			| None -> raise(Empty "e")
			| Some e -> begin
										c.a <- None;
										e
									end
end;;

let cO = ContainerOption.create();;
ContainerOption.put(1, cO);;
ContainerOption.take cO;;


module ContainerList = 
struct
	type 'a t = { mutable n : int; mutable a : 'a list }
	exception Empty of string
	exception Full of string
	
	let create() = { n = 0; a = [] }
	
	let put (e, c) = 
		match c.n with
		| 0 -> begin	c.a <- [e]; c.n <- c.n + 1 end
		| _ -> raise (Full "f")
	
	let take c = 
		match c.n with
		| 0 -> raise (Empty "e")
		| _ -> begin c.n <- c.n - 1; c.a end

end;;

let cL = ContainerList.create();;
ContainerList.put(1, cL);;
ContainerList.take cL;;