From 17a0dccfe91d6f837ce285e62b8d843720f8c1a1 Mon Sep 17 00:00:00 2001 From: Gaëtan Gilbert Date: Fri, 16 Feb 2018 15:44:44 +0100 Subject: Allow using cumulativity without forcing strict constraints. Previously [fun x : Ind@{i} => x : Ind@{j}] with Ind some cumulative inductive would try to generate a constraint [i = j] and use cumulativity only if this resulted in an inconsistency. This is confusingly different from the behaviour with [Type] and means cumulativity can only be used to lift between universes related by strict inequalities. (This isn't a kernel restriction so there might be some workaround to send the kernel the right constraints, but not in a nice way.) See modified test for more details of what is now possible. Technical notes: When universe constraints were inferred by comparing the shape of terms without reduction, cumulativity was not used and so too-strict equality constraints were generated. Then in order to use cumulativity we had to make this comparison fail to fall back to full conversion. When unifiying 2 instances of a cumulative inductive type, if there are any Irrelevant universes we try to unify them if they are flexible. --- kernel/names.mli | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'kernel/names.mli') diff --git a/kernel/names.mli b/kernel/names.mli index 209826c1f..ffd96781b 100644 --- a/kernel/names.mli +++ b/kernel/names.mli @@ -500,6 +500,13 @@ val constructor_user_hash : constructor -> int val constructor_syntactic_ord : constructor -> constructor -> int val constructor_syntactic_hash : constructor -> int +(** {6 Global reference is a kernel side type for all references together } *) +type global_reference = + | VarRef of variable (** A reference to the section-context. *) + | ConstRef of Constant.t (** A reference to the environment. *) + | IndRef of inductive (** A reference to an inductive type. *) + | ConstructRef of constructor (** A reference to a constructor of an inductive type. *) + (** Better to have it here that in Closure, since required in grammar.cma *) type evaluable_global_reference = | EvalVarRef of Id.t -- cgit v1.2.3