-let fold_tac ~reduction ~also_in_hypotheses ~term (proof,goal) =
- let curi,metasenv,pbo,pty = proof in
- let metano,context,ty = CicUtil.lookup_meta goal metasenv in
- let term' = reduction context term in
- (* We don't know if [term] is a subterm of [ty] or a subterm of *)
- (* the type of one metavariable. So we replace it everywhere. *)
- (*CSC: ma si potrebbe ovviare al problema. Ma non credo *)
- (*CSC: che si guadagni nulla in fatto di efficienza. *)
- let replace =
- ProofEngineReduction.replace ~equality:(=) ~what:[term'] ~with_what:[term]
- in
- let ty' = replace ty in
- let metasenv' =
- let context' =
- if also_in_hypotheses then
- List.map
- (function
- Some (n,Cic.Decl t) -> Some (n,Cic.Decl (replace t))
- | Some (n,Cic.Def (t,None)) -> Some (n,Cic.Def ((replace t),None))
- | None -> None
- | Some (_,Cic.Def (_,Some _)) -> assert false
- ) context
- else
- context
- in
- List.map
- (function
- (n,_,_) when n = metano -> (metano,context',ty')
- | _ as t -> t
- ) metasenv
-
+let reduce_tac ~pattern =
+ mk_tactic (reduction_tac ~reduction:ProofEngineReduction.reduce ~pattern);;
+
+let whd_tac ~pattern =
+ mk_tactic (reduction_tac ~reduction:CicReduction.whd ~pattern);;
+
+let normalize_tac ~pattern =
+ mk_tactic (reduction_tac ~reduction:CicReduction.normalize ~pattern);;
+
+exception NotConvertible
+
+(* Note: this code is almost identical to reduction_tac and
+* it could be unified by making the change function a callback *)
+(* CSC: with_what is parsed in the context of the goal, but it should replace
+ something that lives in a completely different context. Thus we
+ perform a delift + lift phase to move it in the right context. However,
+ in this way the tactic is less powerful than expected: with_what cannot
+ reference variables that are local to the term that is going to be
+ replaced. To fix this we should parse with_what in the context of the
+ term(s) to be replaced. *)
+let change_tac ~pattern with_what =
+ let change_tac ~pattern ~with_what (proof, goal) =
+ let curi,metasenv,pbo,pty = proof in
+ let (metano,context,ty) as conjecture = CicUtil.lookup_meta goal metasenv in
+ let context_len = List.length context in
+ let change context'_len where terms =
+ if terms = [] then where
+ else
+ let terms, terms' =
+ List.split
+ (List.map
+ (fun (context_of_t, t) ->
+ let context_of_t_len = List.length context_of_t in
+ let with_what_in_context' =
+ if context_len > context'_len then
+ begin
+ let with_what,subst,metasenv' =
+ CicMetaSubst.delift_rels [] metasenv
+ (context_len - context'_len) with_what
+ in
+ assert (subst = []);
+ assert (metasenv = metasenv');
+ with_what
+ end
+ else
+ with_what in
+ let with_what_in_context_of_t =
+ if context_of_t_len > context'_len then
+ CicSubstitution.lift (context_of_t_len - context'_len)
+ with_what_in_context'
+ else
+ with_what in
+ let _,u =
+ CicTypeChecker.type_of_aux' metasenv context_of_t with_what
+ CicUniv.empty_ugraph in
+ let b,_ =
+ CicReduction.are_convertible ~metasenv context_of_t t with_what u in
+ if b then
+ t, with_what_in_context_of_t
+ else
+ raise NotConvertible) terms)