diff options
Diffstat (limited to 'contrib')
| -rw-r--r-- | contrib/subtac/subtac_classes.ml | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/contrib/subtac/subtac_classes.ml b/contrib/subtac/subtac_classes.ml index cbfec12df4..15729b6266 100644 --- a/contrib/subtac/subtac_classes.ml +++ b/contrib/subtac/subtac_classes.ml @@ -137,11 +137,17 @@ let new_instance ?(global=false) ctx (instid, bk, cl) props ?(generalize=true) p let sigma = Evd.evars_of !isevars in let subst = List.map (Evarutil.nf_evar sigma) subst in let subst = - let props = match props with CRecord (loc, _, fs) -> fs - | _ -> errorlabstrm "new_instance" (Pp.str "Expected a record declaration for the instance body") + let props = + match props with + | CRecord (loc, _, fs) -> + if List.length fs > List.length k.cl_props then + Classes.mismatched_props env' (List.map snd fs) k.cl_props; + fs + | _ -> + if List.length k.cl_props <> 1 then + errorlabstrm "new_instance" (Pp.str "Expected a definition for the instance body") + else [(dummy_loc, Nameops.out_name (pi1 (List.hd k.cl_props))), props] in - if List.length props > List.length k.cl_props then - Classes.mismatched_props env' (List.map snd props) k.cl_props; match k.cl_props with | [(na,b,ty)] -> let term = match props with [] -> CHole (Util.dummy_loc, None) | [(_,f)] -> f | _ -> assert false in |