diff options
Diffstat (limited to 'pretyping/evarconv.ml')
| -rw-r--r-- | pretyping/evarconv.ml | 27 |
1 files changed, 26 insertions, 1 deletions
diff --git a/pretyping/evarconv.ml b/pretyping/evarconv.ml index 42aaf3a22..af84b70a3 100644 --- a/pretyping/evarconv.ml +++ b/pretyping/evarconv.ml @@ -42,6 +42,31 @@ let _ = Goptions.declare_bool_option { Goptions.optwrite = (fun a -> debug_unification:=a); } +(*******************************************) +(* Functions to deal with impossible cases *) +(*******************************************) +(* XXX: we would like to search for this with late binding + "data.id.type" etc... *) +let impossible_default_case () = + let c, ctx = Universes.fresh_global_instance (Global.env()) (Globnames.ConstRef Coqlib.id) in + let (_, u) = Term.destConst c in + Some (c, Term.mkConstU (Coqlib.type_of_id, u), ctx) + +let coq_unit_judge = + let open Environ in + let make_judge c t = make_judge (EConstr.of_constr c) (EConstr.of_constr t) in + let na1 = Name (Id.of_string "A") in + let na2 = Name (Id.of_string "H") in + fun () -> + match impossible_default_case () with + | Some (id, type_of_id, ctx) -> + make_judge id type_of_id, ctx + | None -> + (* In case the constants id/ID are not defined *) + Environ.make_judge (mkLambda (na1,mkProp,mkLambda(na2,mkRel 1,mkRel 1))) + (mkProd (na1,mkProp,mkArrow (mkRel 1) (mkRel 2))), + Univ.ContextSet.empty + let unfold_projection env evd ts p c = let cst = Projection.constant p in if is_transparent_constant ts cst then @@ -351,7 +376,7 @@ let rec evar_conv_x ts env evd pbty term1 term2 = match ground_test with | Some result -> result | None -> - (* Until pattern-unification is used consistently, use nohdbeta to not + (* Until pattern-unification is used consistently, use nohdbeta to not destroy beta-redexes that can be used for 1st-order unification *) let term1 = apprec_nohdbeta (fst ts) env evd term1 in let term2 = apprec_nohdbeta (fst ts) env evd term2 in |