Using 4.01, outa the box, with -fglasgow-exts.
I get the following complaint:
Main.hs:25:
No instance for `Probe (Trans DLX_Op (DLX_Cell DLXReg Int))'
arising from use of `processor' at Main.hs:25
Now, scanning the relevant .hi files, I have:
instance __forall [_a] {PrelBase.Show _a} => {Probe.Probe (DLX_Trans _a)}
where DLX_Trans is defined as follows (again, from the .hi file):
type DLX_Trans _rxQ = Trans.Trans DLX_Op.DLX_Op (DLXCell _rxQ) ;
and DLXCell is defined as follows:
type DLXCell _rxS = DLX_Cell.DLX_Cell DLX_Reg.DLXReg _rxS ;
Doing a little textual substitution, I get:
instance __forall [_a] {PrelBase.Show _a} => {Probe.Probe(Trans.Trans DLX_Op.DLX_Op
(DLX_Cell.DLX_Cell DLX_Reg.DLXReg _a))}
which sure looks like it satisfies the instance request (all the mentioned modules are
directly
imported in Main.hs). Hugs accepts the same program, no complaints. Iz GHC bug?
--Jeff
