1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
|
(************************************************************************)
(* v * The Coq Proof Assistant / The Coq Development Team *)
(* <O___,, * INRIA - CNRS - LIX - LRI - PPS - Copyright 1999-2010 *)
(* \VV/ **************************************************************)
(* // * This file is distributed under the terms of the *)
(* * GNU Lesser General Public License Version 2.1 *)
(************************************************************************)
open Util
open Names
open Term
open Evd
open Evarutil
open Sign
open Refiner
(******************************************)
(* Instantiation of existential variables *)
(******************************************)
let depends_on_evar evk _ (pbty,_,t1,t2) =
try head_evar t1 = evk
with NoHeadEvar ->
try head_evar t2 = evk
with NoHeadEvar -> false
let define_and_solve_constraints evk c evd =
try
let evd = define evk c evd in
let (evd,pbs) = extract_changed_conv_pbs evd (depends_on_evar evk) in
fst (List.fold_left
(fun (evd,b as p) (pbty,env,t1,t2) ->
if b then Evarconv.evar_conv_x env evd pbty t1 t2 else p) (evd,true)
pbs)
with e when Pretype_errors.precatchable_exception e ->
error "Instance does not satisfy constraints."
let w_refine (evk,evi) (ltac_var,rawc) sigma =
if Evd.is_defined sigma evk then
error "Instantiate called on already-defined evar";
let env = Evd.evar_env evi in
let sigma',typed_c =
try Pretyping.Default.understand_ltac true sigma env ltac_var
(Pretyping.OfType (Some evi.evar_concl)) rawc
with _ ->
let loc = Glob_term.loc_of_glob_constr rawc in
user_err_loc
(loc,"",Pp.str ("Instance is not well-typed in the environment of " ^
string_of_existential evk))
in
define_and_solve_constraints evk typed_c (evars_reset_evd sigma' sigma)
(* vernac command Existential *)
(* Main component of vernac command Existential *)
let instantiate_pf_com evk com sigma =
let evi = Evd.find sigma evk in
let env = Evd.evar_env evi in
let rawc = Constrintern.intern_constr sigma env com in
let sigma' = w_refine (evk,evi) (([],[]),rawc) sigma in
sigma'
|