[m-rev.] Another compiler bug with almost the same code

[Volker Wysk]

Hi

The following, slightly modified code leads to another compiler bug (so it
seems):


:- pred with_connection(pred(int, T, io, io), T, io, io).
%:- mode with_connection(pred(in, out, di, uo) is det,      out, di, uo) is
det.
:- mode with_connection(pred(in, out, di, uo) is cc_multi, out, di, uo) is
cc_multi.

with_connection(Pred, PRes, !IO) :-

    Cleanup =
        (pred(io.ok::out, !.IO1::di, !:IO1::uo) is cc_multi :-
            !:IO1 = !.IO1),

    exception.finally(
        Pred(1),    % Line 28
        PRes,
        Cleanup,
        _CleanupRes,
        !IO).


Even though the second mode line is commented out, it doesn't compile:


finally.m:028: In clause for predicate `with_connection'/4:
finally.m:028:   in argument 1 of call to predicate `exception.finally'/6:
finally.m:028:   in unification of argument
finally.m:028:   and term `Pred(V_21)':
finally.m:028:   type error in argument of higher-order term (with arity 1).
finally.m:028:   Functor (Pred) has type
finally.m:028:     some [T] (pred(int, T, io.state, io.state)),
finally.m:028:   expected type was
finally.m:028:     func(V_5) = V_6.


Why is the expected type a function? That must be wrong.


Cheers,
Volker