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|
(* TEST
* expect
*)
type t = { x : int; self : t };;
[%%expect {|
type t = { x : int; self : t; }
|}];;
let rec x = 1
and u = Some { t with x = 2 }
and t = { x; self = t }
(* We have carefully placed `u` before `t` here,
so that the copy { t with .. }, if accepted,
is evaluated before 't' is initialized -- making
the assertion below fail, typically aborting
with a segmentation fault.
If you exchange the declaration orders of `u` and `t`,
and the static check accepts this example, then `t`
is initialized first and the assertion succeeds. *)
let () = match u with
| None -> assert false
| Some {x = _; self} -> assert (self.x = t.x)
[%%expect {|
Line 2, characters 8-29:
2 | and u = Some { t with x = 2 }
^^^^^^^^^^^^^^^^^^^^^
Error: This kind of expression is not allowed as right-hand side of `let rec'
|}];;
|
