theory Fv
imports "../Nominal-General/Nominal2_Atoms"
"Abs" "Perm" "Rsp" "Nominal2_FSet"
begin
(* The bindings data structure:
Bindings are a list of lists of lists of triples.
The first list represents the datatypes defined.
The second list represents the constructors.
The internal list is a list of all the bndings that
concern the constructor.
Every triple consists of a function, the binding and
the body.
Eg:
nominal_datatype
C1
| C2 x y z bind x in z
| C3 x y z bind f x in z bind g y in z
yields:
[
[],
[(NONE, 0, 2)],
[(SOME (Const f), 0, 2), (Some (Const g), 1, 2)]]
A SOME binding has to have a function which takes an appropriate
argument and returns an atom set. A NONE binding has to be on an
argument that is an atom or an atom set.
*)
(*
An overview of the generation of free variables:
1) fv_bn functions are generated only for the non-recursive binds.
An fv_bn for a constructor is a union of values for the arguments:
For an argument x that is in the bn function
- if it is a recursive argument bn' we return: fv_bn' x
- otherwise empty
For an argument x that is not in the bn function
- for atom we return: {atom x}
- for atom set we return: atom ` x
- for a recursive call to type ty' we return: fv_ty' x
with fv of the appropriate type
- otherwise empty
2) fv_ty functions generated for all types being defined:
fv_ty for a constructor is a union of values for the arguments.
For an argument that is bound in a shallow binding we return empty.
For an argument x that bound in a non-recursive deep binding
we return: fv_bn x.
Otherwise we return the free variables of the argument minus the
bound variables of the argument.
The free variables for an argument x are:
- for an atom: {atom x}
- for atom set: atom ` x
- for recursive call to type ty' return: fv_ty' x
- for nominal datatype ty' return: fv_ty' x
The bound variables are a union of results of all bindings that
involve the given argument. For a paricular binding:
- for a binding function bn: bn x
- for a recursive argument of type ty': fv_fy' x
- for nominal datatype ty' return: fv_ty' x
*)
(*
An overview of the generation of alpha-equivalence:
1) alpha_bn relations are generated for binding functions.
An alpha_bn for a constructor is true if a conjunction of
propositions for each argument holds.
For an argument a proposition is build as follows from
th:
- for a recursive argument in the bn function, we return: alpha_bn argl argr
- for a recursive argument for type ty not in bn, we return: alpha_ty argl argr
- for other arguments in the bn function we return: True
- for other arguments not in the bn function we return: argl = argr
2) alpha_ty relations are generated for all the types being defined:
For each constructor we gather all the arguments that are bound,
and for each of those we add a permutation. We associate those
permutations with the bindings. Note that two bindings can have
the same permutation if the arguments being bound are the same.
An alpha_ty for a constructor is true if there exist permutations
as above such that a conjunction of propositions for all arguments holds.
For an argument we allow bindings where only one of the following
holds:
- Argument is bound in some shallow bindings: We return true
- Argument of type ty is bound recursively in some other
arguments [i1, .. in] with one binding function bn.
We return:
(bn argl, (argl, argl_i1, ..., argl_in)) \<approx>gen
\<lambda>(argl,argl1,..,argln) (argr,argr1,..,argrn).
(alpha_ty argl argr) \<and> (alpha_i1 argl1 argr1) \<and> .. \<and> (alpha_in argln argrn)
\<lambda>(arg,arg1,..,argn). (fv_ty arg) \<union> (fv_i1 arg1) \<union> .. \<union> (fv_in argn)
pi
(bn argr, (argr, argr_i1, ..., argr_in))
- Argument is bound in some deep non-recursive bindings.
We return: alpha_bn argl argr
- Argument of type ty has some shallow bindings [b1..bn] and/or
non-recursive bindings [f1 a1, .., fm am], where the bindings
have the permutations p1..pl. We return:
(b1l \<union>..\<union> bnl \<union> f1 a1l \<union>..\<union> fn anl, argl) \<approx>gen
alpha_ty fv_ty (p1 +..+ pl)
(b1r \<union>..\<union> bnr \<union> f1 a1r \<union>..\<union> fn anr, argr)
- Argument has some recursive bindings. The bindings were
already treated in 2nd case so we return: True
- Argument has no bindings and is not bound.
If it is recursive for type ty, we return: alpha_ty argl argr
Otherwise we return: argl = argr
*)
ML {*
datatype alpha_mode = AlphaGen | AlphaRes | AlphaLst;
*}
ML {*
fun atyp_const AlphaGen = @{const_name alpha_gen}
| atyp_const AlphaRes = @{const_name alpha_res}
| atyp_const AlphaLst = @{const_name alpha_lst}
*}
(* TODO: make sure that parser checks that bindings are compatible *)
ML {*
fun alpha_const_for_binds [] = atyp_const AlphaGen
| alpha_const_for_binds ((NONE, _, _, at) :: t) = atyp_const at
| alpha_const_for_binds ((SOME (_, _), _, _, at) :: _) = atyp_const at
*}
ML {*
fun is_atom thy typ =
Sign.of_sort thy (typ, @{sort at})
fun is_atom_set thy (Type ("fun", [t, @{typ bool}])) = is_atom thy t
| is_atom_set _ _ = false;
fun is_atom_fset thy (Type ("FSet.fset", [t])) = is_atom thy t
| is_atom_fset _ _ = false;
*}
(* Like map2, only if the second list is empty passes empty lists insted of error *)
ML {*
fun map2i _ [] [] = []
| map2i f (x :: xs) (y :: ys) = f x y :: map2i f xs ys
| map2i f (x :: xs) [] = f x [] :: map2i f xs []
| map2i _ _ _ = raise UnequalLengths;
*}
(* Finds bindings with the same function and binding, and gathers all
bodys for such pairs
*)
ML {*
fun gather_binds binds =
let
fun gather_binds_cons binds =
let
val common = map (fn (f, bi, _, aty) => (f, bi, aty)) binds
val nodups = distinct (op =) common
fun find_bodys (sf, sbi, sty) =
filter (fn (f, bi, _, aty) => f = sf andalso bi = sbi andalso aty = sty) binds
val bodys = map ((map (fn (_, _, bo, _) => bo)) o find_bodys) nodups
in
nodups ~~ bodys
end
in
map (map gather_binds_cons) binds
end
*}
ML {*
fun un_gather_binds_cons binds =
flat (map (fn (((f, bi, aty), bos), pi) => map (fn bo => ((f, bi, bo, aty), pi)) bos) binds)
*}
ML {*
open Datatype_Aux; (* typ_of_dtyp, DtRec, ... *);
*}
ML {*
(* TODO: It is the same as one in 'nominal_atoms' *)
fun mk_atom ty = Const (@{const_name atom}, ty --> @{typ atom});
val noatoms = @{term "{} :: atom set"};
fun mk_single_atom x = HOLogic.mk_set @{typ atom} [mk_atom (type_of x) $ x];
fun mk_union sets =
fold (fn a => fn b =>
if a = noatoms then b else
if b = noatoms then a else
if a = b then a else
HOLogic.mk_binop @{const_name sup} (a, b)) (rev sets) noatoms;
val mk_inter = foldr1 (HOLogic.mk_binop @{const_name inf})
fun mk_diff a b =
if b = noatoms then a else
if b = a then noatoms else
HOLogic.mk_binop @{const_name minus} (a, b);
fun mk_atom_set t =
let
val ty = fastype_of t;
val atom_ty = HOLogic.dest_setT ty --> @{typ atom};
val img_ty = atom_ty --> ty --> @{typ "atom set"};
in
(Const (@{const_name image}, img_ty) $ Const (@{const_name atom}, atom_ty) $ t)
end;
fun mk_atom_fset t =
let
val ty = fastype_of t;
val atom_ty = dest_fsetT ty --> @{typ atom};
val fmap_ty = atom_ty --> ty --> @{typ "atom fset"};
val fset_to_set = @{term "fset_to_set :: atom fset \<Rightarrow> atom set"}
in
fset_to_set $ ((Const (@{const_name fmap}, fmap_ty) $ Const (@{const_name atom}, atom_ty) $ t))
end;
(* Similar to one in USyntax *)
fun mk_pair (fst, snd) =
let val ty1 = fastype_of fst
val ty2 = fastype_of snd
val c = HOLogic.pair_const ty1 ty2
in c $ fst $ snd
end;
*}
(* Given [fv1, fv2, fv3] creates %(x, y, z). fv1 x u fv2 y u fv3 z *)
ML {*
fun mk_compound_fv fvs =
let
val nos = (length fvs - 1) downto 0;
val fvs_applied = map (fn (fv, no) => fv $ Bound no) (fvs ~~ nos);
val fvs_union = mk_union fvs_applied;
val (tyh :: tys) = rev (map (domain_type o fastype_of) fvs);
fun fold_fun ty t = HOLogic.mk_split (Abs ("", ty, t))
in
fold fold_fun tys (Abs ("", tyh, fvs_union))
end;
*}
(* Given [R1, R2, R3] creates %(x,x'). %(y,y'). %(z,z'). R x x' \<and> R y y' \<and> R z z' *)
ML {*
fun mk_compound_alpha Rs =
let
val nos = (length Rs - 1) downto 0;
val nos2 = (2 * length Rs - 1) downto length Rs;
val Rs_applied = map (fn (R, (no2, no)) => R $ Bound no2 $ Bound no) (Rs ~~ (nos2 ~~ nos));
val Rs_conj = mk_conjl Rs_applied;
val (tyh :: tys) = rev (map (domain_type o fastype_of) Rs);
fun fold_fun ty t = HOLogic.mk_split (Abs ("", ty, t))
val abs_rhs = fold fold_fun tys (Abs ("", tyh, Rs_conj))
in
fold fold_fun tys (Abs ("", tyh, abs_rhs))
end;
*}
ML {*
fun non_rec_binds l =
let
fun is_non_rec (SOME (f, false), _, _, _) = SOME f
| is_non_rec _ = NONE
in
distinct (op =) (map_filter is_non_rec (flat (flat l)))
end
*}
(* We assume no bindings in the type on which bn is defined *)
ML {*
fun fv_bn thy (dt_info : Datatype_Aux.info) fv_frees bn_fvbn (fvbn, (bn, ith_dtyp, args_in_bns)) =
let
val {descr, sorts, ...} = dt_info;
fun nth_dtyp i = typ_of_dtyp descr sorts (DtRec i);
fun fv_bn_constr (cname, dts) args_in_bn =
let
val Ts = map (typ_of_dtyp descr sorts) dts;
val names = Datatype_Prop.make_tnames Ts;
val args = map Free (names ~~ Ts);
val c = Const (cname, Ts ---> (nth_dtyp ith_dtyp));
fun fv_arg ((dt, x), arg_no) =
let
val ty = fastype_of x
(* val _ = tracing ("B 1" ^ PolyML.makestring args_in_bn);*)
(* val _ = tracing ("B 2" ^ PolyML.makestring bn_fvbn);*)
in
case AList.lookup (op=) args_in_bn arg_no of
SOME NONE => @{term "{} :: atom set"}
| SOME (SOME (f : term)) => (the (AList.lookup (op=) bn_fvbn f)) $ x
| NONE =>
if is_atom thy ty then mk_single_atom x else
if is_atom_set thy ty then mk_atom_set x else
if is_atom_fset thy ty then mk_atom_fset x else
if is_rec_type dt then nth fv_frees (body_index dt) $ x else
@{term "{} :: atom set"}
end;
val arg_nos = 0 upto (length dts - 1)
in
HOLogic.mk_Trueprop (HOLogic.mk_eq
(fvbn $ list_comb (c, args), mk_union (map fv_arg (dts ~~ args ~~ arg_nos))))
end;
val (_, (_, _, constrs)) = nth descr ith_dtyp;
val eqs = map2i fv_bn_constr constrs args_in_bns
in
((bn, fvbn), eqs)
end
*}
ML {* print_depth 100 *}
ML {*
fun fv_bns thy dt_info fv_frees rel_bns =
let
fun mk_fvbn_free (bn, ith, _) =
let
val fvbn_name = "fv_" ^ (Long_Name.base_name (fst (dest_Const bn)));
in
(fvbn_name, Free (fvbn_name, fastype_of (nth fv_frees ith)))
end;
val (fvbn_names, fvbn_frees) = split_list (map mk_fvbn_free rel_bns);
val bn_fvbn = (map (fn (bn, _, _) => bn) rel_bns) ~~ fvbn_frees
val (l1, l2) = split_list (map (fv_bn thy dt_info fv_frees bn_fvbn) (fvbn_frees ~~ rel_bns));
in
(l1, (fvbn_names ~~ l2))
end
*}
ML {*
fun alpha_bn (dt_info : Datatype_Aux.info) alpha_frees bn_alphabn ((bn, ith_dtyp, args_in_bns), (alpha_bn_free, _ (*is_rec*) )) =
let
val {descr, sorts, ...} = dt_info;
fun nth_dtyp i = typ_of_dtyp descr sorts (DtRec i);
fun alpha_bn_constr (cname, dts) args_in_bn =
let
val Ts = map (typ_of_dtyp descr sorts) dts;
val names = Name.variant_list ["pi"] (Datatype_Prop.make_tnames Ts);
val names2 = Name.variant_list ("pi" :: names) (Datatype_Prop.make_tnames Ts);
val args = map Free (names ~~ Ts);
val args2 = map Free (names2 ~~ Ts);
val c = Const (cname, Ts ---> (nth_dtyp ith_dtyp));
val rhs = HOLogic.mk_Trueprop
(alpha_bn_free $ (list_comb (c, args)) $ (list_comb (c, args2)));
fun lhs_arg ((dt, arg_no), (arg, arg2)) =
case AList.lookup (op=) args_in_bn arg_no of
SOME NONE => @{term True}
| SOME (SOME f) => (the (AList.lookup (op=) bn_alphabn f)) $ arg $ arg2
| NONE =>
if is_rec_type dt then (nth alpha_frees (body_index dt)) $ arg $ arg2
else HOLogic.mk_eq (arg, arg2)
val arg_nos = 0 upto (length dts - 1)
val lhss = mk_conjl (map lhs_arg (dts ~~ arg_nos ~~ (args ~~ args2)))
val eq = Logic.mk_implies (HOLogic.mk_Trueprop lhss, rhs)
in
eq
end
val (_, (_, _, constrs)) = nth descr ith_dtyp;
val eqs = map2i alpha_bn_constr constrs args_in_bns
in
((bn, alpha_bn_free), eqs)
end
*}
ML {*
fun alpha_bns dt_info alpha_frees rel_bns bns_rec =
let
val {descr, sorts, ...} = dt_info;
fun nth_dtyp i = typ_of_dtyp descr sorts (DtRec i);
fun mk_alphabn_free (bn, ith, _) =
let
val alphabn_name = "alpha_" ^ (Long_Name.base_name (fst (dest_Const bn)));
val alphabn_type = nth_dtyp ith --> nth_dtyp ith --> @{typ bool};
val alphabn_free = Free(alphabn_name, alphabn_type);
in
(alphabn_name, alphabn_free)
end;
val (alphabn_names, alphabn_frees) = split_list (map mk_alphabn_free rel_bns);
val bn_alphabn = (map (fn (bn, _, _) => bn) rel_bns) ~~ alphabn_frees;
val pair = split_list (map (alpha_bn dt_info alpha_frees bn_alphabn)
(rel_bns ~~ (alphabn_frees ~~ bns_rec)))
in
(alphabn_names, pair)
end
*}
(* Checks that a list of bindings contains only compatible ones *)
ML {*
fun bns_same l =
length (distinct (op =) (map (fn ((b, _, _, atyp), _) => (b, atyp)) l)) = 1
*}
ML {*
fun setify x =
if fastype_of x = @{typ "atom list"} then
Const (@{const_name set}, @{typ "atom list \<Rightarrow> atom set"}) $ x else x
*}
ML {*
fun define_fv (dt_info : Datatype_Aux.info) bindsall bns lthy =
let
val thy = ProofContext.theory_of lthy;
val {descr, sorts, ...} = dt_info;
fun nth_dtyp i = typ_of_dtyp descr sorts (DtRec i);
val fv_names = Datatype_Prop.indexify_names (map (fn (i, _) =>
"fv_" ^ name_of_typ (nth_dtyp i)) descr);
val fv_types = map (fn (i, _) => nth_dtyp i --> @{typ "atom set"}) descr;
val fv_frees = map Free (fv_names ~~ fv_types);
(* TODO: We need a transitive closure, but instead we do this hack considering
all binding functions as recursive or not *)
val nr_bns =
if (non_rec_binds bindsall) = [] then []
else map (fn (bn, _, _) => bn) bns;
val rel_bns = filter (fn (bn, _, _) => bn mem nr_bns) bns;
val (bn_fv_bns, fv_bn_names_eqs) = fv_bns thy dt_info fv_frees rel_bns;
val fvbns = map snd bn_fv_bns;
val (fv_bn_names, fv_bn_eqs) = split_list fv_bn_names_eqs;
fun fv_constr ith_dtyp (cname, dts) bindcs =
let
val Ts = map (typ_of_dtyp descr sorts) dts;
val bindslen = length bindcs
val pi_strs_same = replicate bindslen "pi"
val pi_strs = Name.variant_list [] pi_strs_same;
val pis = map (fn ps => Free (ps, @{typ perm})) pi_strs;
val bind_pis_gath = bindcs ~~ pis;
val bind_pis = un_gather_binds_cons bind_pis_gath;
val bindcs = map fst bind_pis;
val names = Name.variant_list pi_strs (Datatype_Prop.make_tnames Ts);
val args = map Free (names ~~ Ts);
val c = Const (cname, Ts ---> (nth_dtyp ith_dtyp));
val fv_c = nth fv_frees ith_dtyp;
val arg_nos = 0 upto (length dts - 1)
fun fv_bind args (NONE, i, _, _) =
if is_rec_type (nth dts i) then (nth fv_frees (body_index (nth dts i))) $ (nth args i) else
if ((is_atom thy) o fastype_of) (nth args i) then mk_single_atom (nth args i) else
if ((is_atom_set thy) o fastype_of) (nth args i) then mk_atom_set (nth args i) else
if ((is_atom_fset thy) o fastype_of) (nth args i) then mk_atom_fset (nth args i) else
(* TODO goes the code for preiously defined nominal datatypes *)
@{term "{} :: atom set"}
| fv_bind args (SOME (f, _), i, _, _) = f $ (nth args i)
fun fv_binds_as_set args relevant = mk_union (map (setify o fv_bind args) relevant)
fun find_nonrec_binder j (SOME (f, false), i, _, _) = if i = j then SOME f else NONE
| find_nonrec_binder _ _ = NONE
fun fv_arg ((dt, x), arg_no) =
case get_first (find_nonrec_binder arg_no) bindcs of
SOME f =>
(case get_first (fn (x, y) => if x = f then SOME y else NONE) bn_fv_bns of
SOME fv_bn => fv_bn $ x
| NONE => error "bn specified in a non-rec binding but not in bn list")
| NONE =>
let
val arg =
if is_rec_type dt then nth fv_frees (body_index dt) $ x else
if ((is_atom thy) o fastype_of) x then mk_single_atom x else
if ((is_atom_set thy) o fastype_of) x then mk_atom_set x else
if ((is_atom_fset thy) o fastype_of) x then mk_atom_fset x else
(* TODO goes the code for preiously defined nominal datatypes *)
@{term "{} :: atom set"};
(* If i = j then we generate it only once *)
val relevant = filter (fn (_, i, j, _) => ((i = arg_no) orelse (j = arg_no))) bindcs;
val sub = fv_binds_as_set args relevant
in
mk_diff arg sub
end;
val fv_eq = HOLogic.mk_Trueprop (HOLogic.mk_eq
(fv_c $ list_comb (c, args), mk_union (map fv_arg (dts ~~ args ~~ arg_nos))))
in
fv_eq
end;
fun fv_eq (i, (_, _, constrs)) binds = map2i (fv_constr i) constrs binds;
val fveqs = map2i fv_eq descr (gather_binds bindsall)
val fv_eqs_perfv = fveqs
val rel_bns_nos = map (fn (_, i, _) => i) rel_bns;
fun filter_fun (_, b) = b mem rel_bns_nos;
val all_fvs = (fv_names ~~ fv_eqs_perfv) ~~ (0 upto (length fv_names - 1))
val (fv_names_fst, fv_eqs_fst) = apsnd flat (split_list (map fst (filter_out filter_fun all_fvs)))
val (fv_names_snd, fv_eqs_snd) = apsnd flat (split_list (map fst (filter filter_fun all_fvs)))
val fv_eqs_all = fv_eqs_fst @ (flat fv_bn_eqs);
val fv_names_all = fv_names_fst @ fv_bn_names;
val add_binds = map (fn x => (Attrib.empty_binding, x))
(* Function_Fun.add_fun Function_Common.default_config ... true *)
val (fvs, lthy') = (Primrec.add_primrec
(map (fn s => (Binding.name s, NONE, NoSyn)) fv_names_all) (add_binds fv_eqs_all) lthy)
val (fvs2, lthy'') =
if fv_eqs_snd = [] then (([], []), lthy') else
(Primrec.add_primrec
(map (fn s => (Binding.name s, NONE, NoSyn)) fv_names_snd) (add_binds fv_eqs_snd) lthy')
val ordered_fvs = fv_frees @ fvbns;
val all_fvs = (fst fvs @ fst fvs2, snd fvs @ snd fvs2)
in
((all_fvs, ordered_fvs), lthy'')
end
*}
ML {*
fun define_alpha (dt_info : Datatype_Aux.info) bindsall bns fv_frees lthy =
let
val thy = ProofContext.theory_of lthy;
val {descr, sorts, ...} = dt_info;
fun nth_dtyp i = typ_of_dtyp descr sorts (DtRec i);
(* TODO: We need a transitive closure, but instead we do this hack considering
all binding functions as recursive or not *)
val nr_bns =
if (non_rec_binds bindsall) = [] then []
else map (fn (bn, _, _) => bn) bns;
val alpha_names = Datatype_Prop.indexify_names (map (fn (i, _) =>
"alpha_" ^ name_of_typ (nth_dtyp i)) descr);
val alpha_types = map (fn (i, _) => nth_dtyp i --> nth_dtyp i --> @{typ bool}) descr;
val alpha_frees = map Free (alpha_names ~~ alpha_types);
(* We assume that a bn is either recursive or not *)
val bns_rec = map (fn (bn, _, _) => not (bn mem nr_bns)) bns;
val (alpha_bn_names, (bn_alpha_bns, alpha_bn_eqs)) =
alpha_bns dt_info alpha_frees bns bns_rec
val alpha_bn_frees = map snd bn_alpha_bns;
val alpha_bn_types = map fastype_of alpha_bn_frees;
fun alpha_constr ith_dtyp (cname, dts) bindcs =
let
val Ts = map (typ_of_dtyp descr sorts) dts;
val bindslen = length bindcs
val pi_strs_same = replicate bindslen "pi"
val pi_strs = Name.variant_list [] pi_strs_same;
val pis = map (fn ps => Free (ps, @{typ perm})) pi_strs;
val bind_pis_gath = bindcs ~~ pis;
val bind_pis = un_gather_binds_cons bind_pis_gath;
val names = Name.variant_list pi_strs (Datatype_Prop.make_tnames Ts);
val args = map Free (names ~~ Ts);
val names2 = Name.variant_list (pi_strs @ names) (Datatype_Prop.make_tnames Ts);
val args2 = map Free (names2 ~~ Ts);
val c = Const (cname, Ts ---> (nth_dtyp ith_dtyp));
val alpha = nth alpha_frees ith_dtyp;
val arg_nos = 0 upto (length dts - 1)
fun fv_bind args (NONE, i, _, _) =
if is_rec_type (nth dts i) then (nth fv_frees (body_index (nth dts i))) $ (nth args i) else
if ((is_atom thy) o fastype_of) (nth args i) then mk_single_atom (nth args i) else
if ((is_atom_set thy) o fastype_of) (nth args i) then mk_atom_set (nth args i) else
if ((is_atom_fset thy) o fastype_of) (nth args i) then mk_atom_fset (nth args i) else
(* TODO goes the code for preiously defined nominal datatypes *)
@{term "{} :: atom set"}
| fv_bind args (SOME (f, _), i, _, _) = f $ (nth args i)
fun fv_binds args relevant = mk_union (map (fv_bind args) relevant)
val alpha_rhs =
HOLogic.mk_Trueprop (alpha $ (list_comb (c, args)) $ (list_comb (c, args2)));
fun alpha_arg ((dt, arg_no), (arg, arg2)) =
let
val rel_in_simp_binds = filter (fn ((NONE, i, _, _), _) => i = arg_no | _ => false) bind_pis;
val rel_in_comp_binds = filter (fn ((SOME _, i, _, _), _) => i = arg_no | _ => false) bind_pis;
val rel_has_binds = filter (fn ((NONE, _, j, _), _) => j = arg_no
| ((SOME (_, false), _, j, _), _) => j = arg_no
| _ => false) bind_pis;
val rel_has_rec_binds = filter
(fn ((SOME (_, true), _, j, _), _) => j = arg_no | _ => false) bind_pis;
in
case (rel_in_simp_binds, rel_in_comp_binds, rel_has_binds, rel_has_rec_binds) of
([], [], [], []) =>
if is_rec_type dt then (nth alpha_frees (body_index dt) $ arg $ arg2)
else (HOLogic.mk_eq (arg, arg2))
| (_, [], [], []) => @{term True}
| ([], [], [], _) => @{term True}
| ([], ((((SOME (bn, is_rec)), _, _, atyp), _) :: _), [], []) =>
if not (bns_same rel_in_comp_binds) then error "incompatible bindings for an argument" else
if is_rec then
let
val (rbinds, rpis) = split_list rel_in_comp_binds
val bound_in_nos = map (fn (_, _, i, _) => i) rbinds
val bound_in_ty_nos = map (fn i => body_index (nth dts i)) bound_in_nos;
val bound_args = arg :: map (nth args) bound_in_nos;
val bound_args2 = arg2 :: map (nth args2) bound_in_nos;
val lhs_binds = fv_binds args rbinds
val lhs_arg = foldr1 HOLogic.mk_prod bound_args
val lhs = mk_pair (lhs_binds, lhs_arg);
val rhs_binds = fv_binds args2 rbinds;
val rhs_arg = foldr1 HOLogic.mk_prod bound_args2;
val rhs = mk_pair (rhs_binds, rhs_arg);
val fvs = map (nth fv_frees) ((body_index dt) :: bound_in_ty_nos);
val fv = mk_compound_fv fvs;
val alphas = map (nth alpha_frees) ((body_index dt) :: bound_in_ty_nos);
val alpha = mk_compound_alpha alphas;
val pi = foldr1 (uncurry mk_plus) (distinct (op =) rpis);
val alpha_gen_pre = Const (atyp_const atyp, dummyT) $ lhs $ alpha $ fv $ pi $ rhs;
val alpha_gen = Syntax.check_term lthy alpha_gen_pre
in
alpha_gen
end
else
let
val alpha_bn_const =
nth alpha_bn_frees (find_index (fn (b, _, _) => b = bn) bns)
in
alpha_bn_const $ arg $ arg2
end
| ([], [], relevant, []) =>
let
val (rbinds, rpis) = split_list relevant
val lhs_binds = fv_binds args rbinds
val lhs = mk_pair (lhs_binds, arg);
val rhs_binds = fv_binds args2 rbinds;
val rhs = mk_pair (rhs_binds, arg2);
val alpha = nth alpha_frees (body_index dt);
val fv = nth fv_frees (body_index dt);
val pi = foldr1 (uncurry mk_plus) (distinct (op =) rpis);
val alpha_const = alpha_const_for_binds rbinds;
val alpha_gen_pre = Const (alpha_const, dummyT) $ lhs $ alpha $ fv $ pi $ rhs;
val alpha_gen = Syntax.check_term lthy alpha_gen_pre
in
alpha_gen
end
| _ => error "Fv.alpha: not supported binding structure"
end
val alphas = map alpha_arg (dts ~~ arg_nos ~~ (args ~~ args2))
val alpha_lhss = mk_conjl alphas
val alpha_lhss_ex =
fold (fn pi_str => fn t => HOLogic.mk_exists (pi_str, @{typ perm}, t)) pi_strs alpha_lhss
val alpha_eq = Logic.mk_implies (HOLogic.mk_Trueprop alpha_lhss_ex, alpha_rhs)
in
alpha_eq
end;
fun alpha_eq (i, (_, _, constrs)) binds = map2i (alpha_constr i) constrs binds;
val alphaeqs = map2i alpha_eq descr (gather_binds bindsall)
val alpha_eqs = flat alphaeqs
val add_binds = map (fn x => (Attrib.empty_binding, x))
val (alphas, lthy') = (Inductive.add_inductive_i
{quiet_mode = true, verbose = false, alt_name = Binding.empty,
coind = false, no_elim = false, no_ind = false, skip_mono = true, fork_mono = false}
(map2 (fn x => fn y => ((Binding.name x, y), NoSyn)) (alpha_names @ alpha_bn_names)
(alpha_types @ alpha_bn_types)) []
(add_binds (alpha_eqs @ flat alpha_bn_eqs)) [] lthy)
in
(alphas, lthy')
end
*}
ML {*
fun define_fv_alpha_export dt binds bns ctxt =
let
val (((fv_ts_loc, fv_def_loc), ord_fv_ts_loc), ctxt') =
define_fv dt binds bns ctxt;
val (alpha, ctxt'') =
define_alpha dt binds bns fv_ts_loc ctxt';
val alpha_ts_loc = #preds alpha
val alpha_induct_loc = #induct alpha
val alpha_intros_loc = #intrs alpha;
val alpha_cases_loc = #elims alpha
val morphism = ProofContext.export_morphism ctxt'' ctxt;
val fv_ts = map (Morphism.term morphism) fv_ts_loc;
val ord_fv_ts = map (Morphism.term morphism) ord_fv_ts_loc;
val fv_def = Morphism.fact morphism fv_def_loc;
val alpha_ts = map (Morphism.term morphism) alpha_ts_loc;
val alpha_induct = Morphism.thm morphism alpha_induct_loc;
val alpha_intros = Morphism.fact morphism alpha_intros_loc
val alpha_cases = Morphism.fact morphism alpha_cases_loc
in
((((fv_ts, ord_fv_ts), fv_def), ((alpha_ts, alpha_intros), (alpha_cases, alpha_induct))), ctxt'')
end;
*}
end