diff options
Diffstat (limited to 'kernel/indTyping.ml')
| -rw-r--r-- | kernel/indTyping.ml | 17 |
1 files changed, 12 insertions, 5 deletions
diff --git a/kernel/indTyping.ml b/kernel/indTyping.ml index e9687991c0..179353d3f0 100644 --- a/kernel/indTyping.ml +++ b/kernel/indTyping.ml @@ -134,11 +134,18 @@ let check_constructors env_ar_par isrecord params lc (arity,indices,univ_info) = (* Empty type: all OK *) | 0 -> univ_info - (* SProp primitive records are OK, if we squash and become fakerecord also OK *) - | 1 when isrecord -> univ_info - - (* Unit and identity types must squash if SProp *) - | 1 -> check_univ_leq env_ar_par Univ.Universe.type0m univ_info + | 1 -> + (* SProp primitive records are OK, if we squash and become fakerecord also OK *) + if isrecord then univ_info + (* 1 constructor with no arguments also OK in SProp (to make + things easier on ourselves when reducing we forbid letins) *) + else if (Environ.typing_flags env_ar_par).allow_uip + && fst (splayed_lc.(0)) = [] + && List.for_all Context.Rel.Declaration.is_local_assum params + then univ_info + (* 1 constructor with arguments must squash if SProp + (we could allow arguments in SProp but the reduction rule is a pain) *) + else check_univ_leq env_ar_par Univ.Universe.type0m univ_info (* More than 1 constructor: must squash if Prop/SProp *) | _ -> check_univ_leq env_ar_par Univ.Universe.type0 univ_info |