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[Caml-list] Creating mutually dependent objects?
- Thorsten Ohl
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| Date: | -- (:) |
| From: | Thorsten Ohl <ohl@p...> |
| Subject: | [Caml-list] Creating mutually dependent objects? |
I need to create tuples of mutually dependent objects. A working
implementation adds a mutable instance variable that is updated after
all objects in a tuple have been created. With a little bit of work,
this variable can then be hidden. However, this is a bit tedious.
Why is the much more elegant approach using `let rec' forbidden?
# class o n o' =
object (_ : 'a)
method o' : 'a = o'
method n : int = n
end;;
class o : int -> 'a -> object ('a) method n : int method o' : 'a end
# let rec o1 = new o 1 o2 and o2 = new o 2 o1;;
Characters 13-23:
let rec o1 = new o 1 o2 and o2 = new o 2 o1;;
^^^^^^^^^^
This kind of expression is not allowed as right-hand side of `let rec'
Is there a chance that this restriction will be lifted or would such
permissiveness undermine type safety?
--
Thorsten Ohl, Physics Dept., Wuerzburg Univ. -- ohl@physik.uni-wuerzburg.de
http://theorie.physik.uni-wuerzburg.de/~ohl/ [<=== PGP public key here]
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