[Caml-list] strange typechecking result

[Matej Kosik <5764c029b688c1c0d24a2e97cd764f@gmail.com>]

Hello,

For one of my modules, the typechecker started to raise strange 
complaints. I was not able to figure out exactly why, but at least I 
wanted to narrow down the problem.

This small program:

   type r1 = {l1 : unit list}

   and r2 = {l2 : int64 list}

   let rec f1 _ =
     ()

   and _ r1 =
     f1 r1.l1

   and _ r2 =
     f1 r2.l2

is rejected by the typechecker with a following error message:

   File "test.ml", line 12, characters 5-10:
   Error: This expression has type int64 list
          but an expression was expected of type unit list

I do not understand why the given program was rejected.

Thanks in advance for any help.
--
Matej Kosik