diff options
| author |  Matthieu Sozeau <mattam@mattam.org> | 2017-04-05 23:17:56 +0200 |
|---|---|---|
| committer |  Matthieu Sozeau <matthieu.sozeau@inria.fr> | 2018-06-15 11:58:56 +0200 |
| commit | 8ab4f8f76958d2603858ad3e4073be61ad38d113 (patch) | |
| tree | 562f52d70b92717acaf0916fd9c0f91cb4ac0d61 /engine/evarutil.mli | |
| parent | 31e13998542941040343cb81787a1d7c865d5b65 (diff) | |
evd: restrict_evar with candidates, can raise NoCandidatesLeft
When restricting an evar with candidates, raise an exception if this
restriction would leave the evar without candidates, i.e. unsolvable.
- evarutil: mark restricted evars as "cleared"
They would otherwise escape being catched by the [advance] function
of clenv, and result in dangling evars not being registered to the shelf.
- engine: restrict_evar marks it cleared, update the future goals
We make the new evar a future goal and remove the old one.
If we did nothing, [unshelve tac] would work correctly as it
uses [Proofview.advance] to find the shelved goals, going through
the cleared evar. But [Unshelve] would fail as it expects only
undefined evars on the shelf and throws away the defined ones.
Diffstat (limited to 'engine/evarutil.mli')
| -rw-r--r-- | engine/evarutil.mli | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/engine/evarutil.mli b/engine/evarutil.mli index c17f3d168..1003c4feb 100644 --- a/engine/evarutil.mli +++ b/engine/evarutil.mli @@ -65,9 +65,6 @@ val new_type_evar : val new_Type : ?rigid:rigid -> env -> evar_map -> evar_map * constr -val restrict_evar : evar_map -> Evar.t -> Filter.t -> - ?src:Evar_kinds.t Loc.located -> constr list option -> evar_map * Evar.t - (** Polymorphic constants *) val new_global : evar_map -> GlobRef.t -> evar_map * constr @@ -223,9 +220,18 @@ raise OccurHypInSimpleClause if the removal breaks dependencies *) type clear_dependency_error = | OccurHypInSimpleClause of Id.t option | EvarTypingBreak of Constr.existential +| NoCandidatesLeft of Evar.t exception ClearDependencyError of Id.t * clear_dependency_error * GlobRef.t option +(** Restrict an undefined evar according to a (sub)filter and candidates. + The evar will be defined if there is only one candidate left, +@raise ClearDependencyError NoCandidatesLeft if the filter turns the candidates + into an empty list. *) + +val restrict_evar : evar_map -> Evar.t -> Filter.t -> + ?src:Evar_kinds.t Loc.located -> constr list option -> evar_map * Evar.t + val clear_hyps_in_evi : env -> evar_map -> named_context_val -> types -> Id.Set.t -> evar_map * named_context_val * types |