diff options
Diffstat (limited to 'pretyping/typeclasses.ml')
| -rw-r--r-- | pretyping/typeclasses.ml | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/pretyping/typeclasses.ml b/pretyping/typeclasses.ml index 96e36b70ba..8d987d0379 100644 --- a/pretyping/typeclasses.ml +++ b/pretyping/typeclasses.ml @@ -272,7 +272,8 @@ let class_info c = with _ -> not_a_class (Global.env()) (constr_of_global c) let instance_constructor cl args = - let pars = fst (list_chop (List.length (fst cl.cl_context)) args) in + let lenpars = List.length (List.filter (fun (na, b, t) -> b = None) (snd cl.cl_context)) in + let pars = fst (list_chop lenpars args) in match cl.cl_impl with | IndRef ind -> applistc (mkConstruct (ind, 1)) args, applistc (mkInd ind) pars |