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(* Author: Pascal Stoop, ETH Zurich
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Author: Andreas Lochbihler, Digital Asset *)
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signature CASE_CONVERTER =
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sig
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val to_case: Proof.context -> (string * string -> bool) -> (string * typ -> int) ->
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thm list -> thm list option
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end;
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structure Case_Converter : CASE_CONVERTER =
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struct
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fun lookup_remove _ _ [] = (NONE, [])
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| lookup_remove eq k ((k', v) :: kvs) =
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if eq (k, k') then (SOME (k', v), kvs)
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else apsnd (cons (k', v)) (lookup_remove eq k kvs)
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fun map_option _ NONE = NONE
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| map_option f (SOME x) = SOME (f x)
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fun mk_abort msg t =
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let
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val T = fastype_of t
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val abort = Const (@{const_name missing_pattern_match}, HOLogic.literalT --> (HOLogic.unitT --> T) --> T)
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in
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abort $ HOLogic.mk_literal msg $ absdummy HOLogic.unitT t
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end
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(* fold_term : (string * typ -> 'a) ->
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(string * typ -> 'a) ->
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(indexname * typ -> 'a) ->
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(int -> 'a) ->
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(string * typ * 'a -> 'a) ->
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('a * 'a -> 'a) ->
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term ->
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'a *)
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fun fold_term const_fun free_fun var_fun bound_fun abs_fun dollar_fun term =
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let
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fun go x = case x of
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Const (s, T) => const_fun (s, T)
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| Free (s, T) => free_fun (s, T)
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| Var (i, T) => var_fun (i, T)
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| Bound n => bound_fun n
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| Abs (s, T, term) => abs_fun (s, T, go term)
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| term1 $ term2 => dollar_fun (go term1, go term2)
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in
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go term
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end;
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datatype term_coordinate = End of typ
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| Coordinate of (string * (int * term_coordinate)) list;
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fun term_coordinate_merge (End T) _ = End T
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| term_coordinate_merge _ (End T) = End T
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| term_coordinate_merge (Coordinate xs) (Coordinate ys) =
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let
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fun merge_consts xs [] = xs
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| merge_consts xs ((s1, (n, y)) :: ys) =
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case List.partition (fn (s2, (m, _)) => s1 = s2 andalso n = m) xs of
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([], xs') => (s1, (n, y)) :: (merge_consts xs' ys)
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| ((_, (_, x)) :: _, xs') => (s1, (n, term_coordinate_merge x y)) :: (merge_consts xs' ys)
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in
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Coordinate (merge_consts xs ys)
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end;
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fun term_to_coordinates P term =
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let
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val (ctr, args) = strip_comb term
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in
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case ctr of Const (s, T) =>
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if P (body_type T |> dest_Type |> fst, s)
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then SOME (End (body_type T))
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else
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let
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fun f (i, t) = term_to_coordinates P t |> map_option (pair i)
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val tcos = map_filter I (map_index f args)
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in
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if null tcos then NONE
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else SOME (Coordinate (map (pair s) tcos))
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end
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| _ => NONE
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end;
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fun coordinates_to_list (End x) = [(x, [])]
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| coordinates_to_list (Coordinate xs) =
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let
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fun f (s, (n, xss)) = map (fn (T, xs) => (T, (s, n) :: xs)) (coordinates_to_list xss)
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in flat (map f xs) end;
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(* AL: TODO: change from term to const_name *)
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fun find_ctr ctr1 xs =
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let
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val const_name = fst o dest_Const
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fun const_equal (ctr1, ctr2) = const_name ctr1 = const_name ctr2
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in
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lookup_remove const_equal ctr1 xs
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end;
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datatype pattern
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= Wildcard
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| Value
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| Split of int * (term * pattern) list * pattern;
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fun pattern_merge Wildcard pat' = pat'
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| pattern_merge Value _ = Value
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| pattern_merge (Split (n, xs, pat)) Wildcard =
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Split (n, map (apsnd (fn pat'' => pattern_merge pat'' Wildcard)) xs, pattern_merge pat Wildcard)
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| pattern_merge (Split _) Value = Value
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| pattern_merge (Split (n, xs, pat)) (Split (m, ys, pat'')) =
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let
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fun merge_consts xs [] = map (apsnd (fn pat => pattern_merge pat Wildcard)) xs
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| merge_consts xs ((ctr, y) :: ys) =
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(case find_ctr ctr xs of
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(SOME (ctr, x), xs) => (ctr, pattern_merge x y) :: merge_consts xs ys
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| (NONE, xs) => (ctr, y) :: merge_consts xs ys
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)
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in
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Split (if n <= 0 then m else n, merge_consts xs ys, pattern_merge pat pat'')
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end
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fun pattern_intersect Wildcard _ = Wildcard
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| pattern_intersect Value pat2 = pat2
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| pattern_intersect (Split _) Wildcard = Wildcard
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| pattern_intersect (Split (n, xs', pat1)) Value =
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Split (n,
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map (apsnd (fn pat1 => pattern_intersect pat1 Value)) xs',
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pattern_intersect pat1 Value)
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| pattern_intersect (Split (n, xs', pat1)) (Split (m, ys, pat2)) =
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Split (if n <= 0 then m else n,
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intersect_consts xs' ys pat1 pat2,
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pattern_intersect pat1 pat2)
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and
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intersect_consts xs [] _ default2 = map (apsnd (fn pat => pattern_intersect pat default2)) xs
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| intersect_consts xs ((ctr, pat2) :: ys) default1 default2 = case find_ctr ctr xs of
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(SOME (ctr, pat1), xs') =>
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(ctr, pattern_merge (pattern_merge (pattern_intersect pat1 pat2) (pattern_intersect default1 pat2))
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(pattern_intersect pat1 default2)) ::
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intersect_consts xs' ys default1 default2
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| (NONE, xs') => (ctr, pattern_intersect default1 pat2) :: (intersect_consts xs' ys default1 default2)
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fun pattern_lookup _ Wildcard = Wildcard
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| pattern_lookup _ Value = Value
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| pattern_lookup [] (Split (n, xs, pat)) =
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Split (n, map (apsnd (pattern_lookup [])) xs, pattern_lookup [] pat)
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| pattern_lookup (term :: terms) (Split (n, xs, pat)) =
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let
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val (ctr, args) = strip_comb term
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fun map_ctr (term, pat) =
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let
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val args = term |> dest_Const |> snd |> binder_types |> map (fn T => Free ("x", T))
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in
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pattern_lookup args pat
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end
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in
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if is_Const ctr then
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case find_ctr ctr xs of (SOME (_, pat'), _) =>
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pattern_lookup terms (pattern_merge (pattern_lookup args pat') (pattern_lookup [] pat))
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| (NONE, _) => pattern_lookup terms pat
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else if length xs < n orelse n <= 0 then
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pattern_lookup terms pat
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else pattern_lookup terms
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(pattern_merge
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(fold pattern_intersect (map map_ctr (tl xs)) (map_ctr (hd xs)))
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(pattern_lookup [] pat))
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end;
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fun pattern_contains terms pat = case pattern_lookup terms pat of
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Wildcard => false
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| Value => true
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| Split _ => raise Match;
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fun pattern_create _ [] = Wildcard
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| pattern_create ctr_count (term :: terms) =
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let
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val (ctr, args) = strip_comb term
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in
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if is_Const ctr then
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Split (ctr_count ctr, [(ctr, pattern_create ctr_count (args @ terms))], Wildcard)
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else Split (0, [], pattern_create ctr_count terms)
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end;
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fun pattern_insert ctr_count terms pat =
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let
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fun new_pattern terms = pattern_insert ctr_count terms (pattern_create ctr_count terms)
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fun aux _ false Wildcard = Wildcard
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| aux terms true Wildcard = if null terms then Value else new_pattern terms
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| aux _ _ Value = Value
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| aux terms modify (Split (n, xs', pat)) =
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let
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val unmodified = (n, map (apsnd (aux [] false)) xs', aux [] false pat)
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in case terms of [] => Split unmodified
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| term :: terms =>
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let
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val (ctr, args) = strip_comb term
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val (m, ys, pat') = unmodified
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in
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if is_Const ctr
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then case find_ctr ctr xs' of
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(SOME (ctr, pat''), xs) =>
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Split (m, (ctr, aux (args @ terms) modify pat'') :: map (apsnd (aux [] false)) xs, pat')
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| (NONE, _) => if modify
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then if m <= 0
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then Split (ctr_count ctr, (ctr, new_pattern (args @ terms)) :: ys, pat')
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else Split (m, (ctr, new_pattern (args @ terms)) :: ys, pat')
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else Split unmodified
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else Split (m, ys, aux terms modify pat)
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end
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end
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in
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aux terms true pat
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end;
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val pattern_empty = Wildcard;
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fun replace_frees lhss rhss typ_list ctxt =
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let
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fun replace_frees_once (lhs, rhs) ctxt =
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let
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val add_frees_list = fold_rev Term.add_frees
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val frees = add_frees_list lhs []
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val (new_frees, ctxt1) = (Ctr_Sugar_Util.mk_Frees "x" (map snd frees) ctxt)
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val (new_frees1, ctxt2) =
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let
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val (dest_frees, types) = split_list (map dest_Free new_frees)
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val (new_frees, ctxt2) = Variable.variant_fixes dest_frees ctxt1
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in
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(map Free (new_frees ~~ types), ctxt2)
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end
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val dict = frees ~~ new_frees1
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fun free_map_fun (s, T) =
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case AList.lookup (op =) dict (s, T) of
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NONE => Free (s, T)
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| SOME x => x
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val map_fun = fold_term Const free_map_fun Var Bound Abs (op $)
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in
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((map map_fun lhs, map_fun rhs), ctxt2)
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end
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fun variant_fixes (def_frees, ctxt) =
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let
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val (dest_frees, types) = split_list (map dest_Free def_frees)
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val (def_frees, ctxt1) = Variable.variant_fixes dest_frees ctxt
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in
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(map Free (def_frees ~~ types), ctxt1)
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end
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val (def_frees, ctxt1) = variant_fixes (Ctr_Sugar_Util.mk_Frees "x" typ_list ctxt)
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val (rhs_frees, ctxt2) = variant_fixes (Ctr_Sugar_Util.mk_Frees "x" typ_list ctxt1)
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val (case_args, ctxt3) = variant_fixes (Ctr_Sugar_Util.mk_Frees "x"
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(map fastype_of (hd lhss)) ctxt2)
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val (new_terms1, ctxt4) = fold_map replace_frees_once (lhss ~~ rhss) ctxt3
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val (lhss1, rhss1) = split_list new_terms1
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in
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(lhss1, rhss1, def_frees ~~ rhs_frees, case_args, ctxt4)
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end;
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fun add_names_in_type (Type (name, Ts)) =
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List.foldr (op o) (Symtab.update (name, ())) (map add_names_in_type Ts)
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| add_names_in_type (TFree _) = I
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| add_names_in_type (TVar _) = I
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fun add_names_in_term (Const (_, T)) = add_names_in_type T
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| add_names_in_term (Free (_, T)) = add_names_in_type T
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| add_names_in_term (Var (_, T)) = add_names_in_type T
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| add_names_in_term (Bound _) = I
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| add_names_in_term (Abs (_, T, body)) =
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add_names_in_type T o add_names_in_term body
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| add_names_in_term (t1 $ t2) = add_names_in_term t1 o add_names_in_term t2
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fun add_type_names terms =
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fold (fn term => fn f => add_names_in_term term o f) terms I
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fun get_split_theorems ctxt =
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Symtab.keys
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#> map_filter (Ctr_Sugar.ctr_sugar_of ctxt)
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#> map #split;
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fun match (Const (s1, _)) (Const (s2, _)) = if s1 = s2 then SOME I else NONE
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| match (Free y) x = SOME (fn z => if z = Free y then x else z)
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| match (pat1 $ pattern2) (t1 $ t2) =
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(case (match pat1 t1, match pattern2 t2) of
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(SOME f, SOME g) => SOME (f o g)
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| _ => NONE
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)
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| match _ _ = NONE;
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fun match_all patterns terms =
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let
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fun combine _ NONE = NONE
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| combine (f_opt, f_opt') (SOME g) =
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case match f_opt f_opt' of SOME f => SOME (f o g) | _ => NONE
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in
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fold_rev combine (patterns ~~ terms) (SOME I)
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end
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fun matches (Const (s1, _)) (Const (s2, _)) = s1 = s2
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| matches (Free _) _ = true
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| matches (pat1 $ pat2) (t1 $ t2) = matches pat1 t1 andalso matches pat2 t2
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| matches _ _ = false;
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fun matches_all patterns terms = forall (uncurry matches) (patterns ~~ terms)
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fun terms_to_case_at ctr_count ctxt (fun_t : term) (default_lhs : term list)
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(pos, (lazy_case_arg, rhs_free))
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((lhss : term list list), (rhss : term list), type_name_fun) =
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let
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fun abort t =
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let
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val fun_name = head_of t |> dest_Const |> fst
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val msg = "Missing pattern in " ^ fun_name ^ "."
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in
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mk_abort msg t
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end;
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(* Step 1 : Eliminate lazy pattern *)
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fun replace_pat_at (n, tcos) pat pats =
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let
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fun map_at _ _ [] = raise Empty
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| map_at n f (x :: xs) = if n > 0
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then apfst (cons x) (map_at (n - 1) f xs)
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else apfst (fn x => x :: xs) (f x)
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fun replace [] pat term = (pat, term)
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| replace ((s1, n) :: tcos) pat term =
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let
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val (ctr, args) = strip_comb term
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in
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case ctr of Const (s2, _) =>
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if s1 = s2
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then apfst (pair ctr #> list_comb) (map_at n (replace tcos pat) args)
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else (term, rhs_free)
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| _ => (term, rhs_free)
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end
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val (part1, (old_pat, part2)) = chop n pats ||> (fn xs => (hd xs, tl xs))
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val (new_pat, old_pat1) = replace tcos pat old_pat
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in
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(part1 @ [new_pat] @ part2, old_pat1)
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end
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val (lhss1, lazy_pats) = map (replace_pat_at pos lazy_case_arg) lhss
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|> split_list
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(* Step 2 : Split patterns *)
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fun split equs =
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let
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fun merge_pattern (Const (s1, T1), Const (s2, _)) =
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if s1 = s2 then SOME (Const (s1, T1)) else NONE
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| merge_pattern (t, Free _) = SOME t
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| merge_pattern (Free _, t) = SOME t
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| merge_pattern (t1l $ t1r, t2l $ t2r) =
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(case (merge_pattern (t1l, t2l), merge_pattern (t1r, t2r)) of
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(SOME t1, SOME t2) => SOME (t1 $ t2)
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| _ => NONE)
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| merge_pattern _ = NONE
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fun merge_patterns pats1 pats2 = case (pats1, pats2) of
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([], []) => SOME []
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| (x :: xs, y :: ys) =>
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(case (merge_pattern (x, y), merge_patterns xs ys) of
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(SOME x, SOME xs) => SOME (x :: xs)
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|
357 |
| _ => NONE
|
|
358 |
)
|
|
359 |
| _ => raise Match
|
|
360 |
fun merge_insert ((lhs1, case_pat), _) [] =
|
|
361 |
[(lhs1, pattern_empty |> pattern_insert ctr_count [case_pat])]
|
|
362 |
| merge_insert ((lhs1, case_pat), rhs) ((lhs2, pat) :: pats) =
|
|
363 |
let
|
|
364 |
val pats = merge_insert ((lhs1, case_pat), rhs) pats
|
|
365 |
val (first_equ_needed, new_lhs) = case merge_patterns lhs1 lhs2 of
|
|
366 |
SOME new_lhs => (not (pattern_contains [case_pat] pat), new_lhs)
|
|
367 |
| NONE => (false, lhs2)
|
|
368 |
val second_equ_needed = not (matches_all lhs1 lhs2)
|
|
369 |
orelse not first_equ_needed
|
|
370 |
val first_equ = if first_equ_needed
|
|
371 |
then [(new_lhs, pattern_insert ctr_count [case_pat] pat)]
|
|
372 |
else []
|
|
373 |
val second_equ = if second_equ_needed
|
|
374 |
then [(lhs2, pat)]
|
|
375 |
else []
|
|
376 |
in
|
|
377 |
first_equ @ second_equ @ pats
|
|
378 |
end
|
|
379 |
in
|
|
380 |
(fold merge_insert equs []
|
|
381 |
|> split_list
|
|
382 |
|> fst) @ [default_lhs]
|
|
383 |
end
|
|
384 |
val lhss2 = split ((lhss1 ~~ lazy_pats) ~~ rhss)
|
|
385 |
|
|
386 |
(* Step 3 : Remove redundant patterns *)
|
|
387 |
fun remove_redundant_lhs lhss =
|
|
388 |
let
|
|
389 |
fun f lhs pat = if pattern_contains lhs pat
|
|
390 |
then ((lhs, false), pat)
|
|
391 |
else ((lhs, true), pattern_insert ctr_count lhs pat)
|
|
392 |
in
|
|
393 |
fold_map f lhss pattern_empty
|
|
394 |
|> fst
|
|
395 |
|> filter snd
|
|
396 |
|> map fst
|
|
397 |
end
|
|
398 |
fun remove_redundant_rhs rhss =
|
|
399 |
let
|
|
400 |
fun f (lhs, rhs) pat = if pattern_contains [lhs] pat
|
|
401 |
then (((lhs, rhs), false), pat)
|
|
402 |
else (((lhs, rhs), true), pattern_insert ctr_count [lhs] pat)
|
|
403 |
in
|
|
404 |
map fst (filter snd (fold_map f rhss pattern_empty |> fst))
|
|
405 |
end
|
|
406 |
val lhss3 = remove_redundant_lhs lhss2
|
|
407 |
|
|
408 |
(* Step 4 : Compute right hand side *)
|
|
409 |
fun subs_fun f = fold_term
|
|
410 |
Const
|
|
411 |
(f o Free)
|
|
412 |
Var
|
|
413 |
Bound
|
|
414 |
Abs
|
|
415 |
(fn (x, y) => f x $ f y)
|
|
416 |
fun find_rhss lhs =
|
|
417 |
let
|
|
418 |
fun f (lhs1, (pat, rhs)) =
|
|
419 |
case match_all lhs1 lhs of NONE => NONE
|
|
420 |
| SOME f => SOME (pat, subs_fun f rhs)
|
|
421 |
in
|
|
422 |
remove_redundant_rhs
|
|
423 |
(map_filter f (lhss1 ~~ (lazy_pats ~~ rhss)) @
|
|
424 |
[(lazy_case_arg, list_comb (fun_t, lhs) |> abort)]
|
|
425 |
)
|
|
426 |
end
|
|
427 |
|
|
428 |
(* Step 5 : make_case of right hand side *)
|
|
429 |
fun make_case ctxt case_arg cases = case cases of
|
|
430 |
[(Free x, rhs)] => subs_fun (fn y => if y = Free x then case_arg else y) rhs
|
|
431 |
| _ => Case_Translation.make_case
|
|
432 |
ctxt
|
|
433 |
Case_Translation.Warning
|
|
434 |
Name.context
|
|
435 |
case_arg
|
|
436 |
cases
|
|
437 |
val type_name_fun = add_type_names lazy_pats o type_name_fun
|
|
438 |
val rhss3 = map ((make_case ctxt lazy_case_arg) o find_rhss) lhss3
|
|
439 |
in
|
|
440 |
(lhss3, rhss3, type_name_fun)
|
|
441 |
end;
|
|
442 |
|
|
443 |
fun terms_to_case ctxt ctr_count (head : term) (lhss : term list list)
|
|
444 |
(rhss : term list) (typ_list : typ list) (poss : (int * (string * int) list) list) =
|
|
445 |
let
|
|
446 |
val (lhss1, rhss1, def_frees, case_args, ctxt1) = replace_frees lhss rhss typ_list ctxt
|
|
447 |
val exec_list = poss ~~ def_frees
|
|
448 |
val (lhss2, rhss2, type_name_fun) = fold_rev
|
|
449 |
(terms_to_case_at ctr_count ctxt1 head case_args) exec_list (lhss1, rhss1, I)
|
|
450 |
fun make_eq_term (lhss, rhs) = (list_comb (head, lhss), rhs)
|
|
451 |
|> HOLogic.mk_eq
|
|
452 |
|> HOLogic.mk_Trueprop
|
|
453 |
in
|
|
454 |
(map make_eq_term (lhss2 ~~ rhss2),
|
|
455 |
get_split_theorems ctxt1 (type_name_fun Symtab.empty),
|
|
456 |
ctxt1)
|
|
457 |
end;
|
|
458 |
|
|
459 |
fun build_case_t replace_ctr ctr_count head lhss rhss ctxt =
|
|
460 |
let
|
|
461 |
val num_eqs = length lhss
|
|
462 |
val _ = if length rhss = num_eqs andalso num_eqs > 0 then ()
|
|
463 |
else raise Fail
|
|
464 |
("expected same number of left-hand sides as right-hand sides\n"
|
|
465 |
^ "and at least one equation")
|
|
466 |
val n = length (hd lhss)
|
|
467 |
val _ = if forall (fn m => length m = n) lhss then ()
|
|
468 |
else raise Fail "expected equal number of arguments"
|
|
469 |
|
|
470 |
fun to_coordinates (n, ts) = case map_filter (term_to_coordinates replace_ctr) ts of
|
|
471 |
[] => NONE
|
|
472 |
| (tco :: tcos) => SOME (n, fold term_coordinate_merge tcos tco |> coordinates_to_list)
|
|
473 |
fun add_T (n, xss) = map (fn (T, xs) => (T, (n, xs))) xss
|
|
474 |
val (typ_list, poss) = lhss
|
|
475 |
|> Ctr_Sugar_Util.transpose
|
|
476 |
|> map_index to_coordinates
|
|
477 |
|> map_filter (map_option add_T)
|
|
478 |
|> flat
|
|
479 |
|> split_list
|
|
480 |
in
|
|
481 |
if null poss then ([], [], ctxt)
|
|
482 |
else terms_to_case ctxt (dest_Const #> ctr_count) head lhss rhss typ_list poss
|
|
483 |
end;
|
|
484 |
|
|
485 |
fun tac ctxt {splits, intros, defs} =
|
|
486 |
let
|
|
487 |
val split_and_subst =
|
|
488 |
split_tac ctxt splits
|
|
489 |
THEN' REPEAT_ALL_NEW (
|
|
490 |
resolve_tac ctxt [@{thm conjI}, @{thm allI}]
|
|
491 |
ORELSE'
|
|
492 |
(resolve_tac ctxt [@{thm impI}] THEN' hyp_subst_tac_thin true ctxt))
|
|
493 |
in
|
|
494 |
(REPEAT_ALL_NEW split_and_subst ORELSE' K all_tac)
|
|
495 |
THEN' (K (Local_Defs.unfold_tac ctxt [@{thm missing_pattern_match_def}]))
|
|
496 |
THEN' (K (Local_Defs.unfold_tac ctxt defs))
|
|
497 |
THEN_ALL_NEW (SOLVED' (resolve_tac ctxt (@{thm refl} :: intros)))
|
|
498 |
end;
|
|
499 |
|
|
500 |
fun to_case _ _ _ [] = NONE
|
|
501 |
| to_case ctxt replace_ctr ctr_count ths =
|
|
502 |
let
|
|
503 |
val strip_eq = Thm.prop_of #> HOLogic.dest_Trueprop #> HOLogic.dest_eq
|
|
504 |
fun import [] ctxt = ([], ctxt)
|
|
505 |
| import (thm :: thms) ctxt =
|
|
506 |
let
|
|
507 |
val fun_ct = strip_eq #> fst #> head_of #> Logic.mk_term #> Thm.cterm_of ctxt
|
|
508 |
val ct = fun_ct thm
|
|
509 |
val cts = map fun_ct thms
|
|
510 |
val pairs = map (fn s => (s,ct)) cts
|
|
511 |
val thms' = map (fn (th,p) => Thm.instantiate (Thm.match p) th) (thms ~~ pairs)
|
|
512 |
in
|
|
513 |
Variable.import true (thm :: thms') ctxt |> apfst snd
|
|
514 |
end
|
|
515 |
|
|
516 |
val (iths, ctxt') = import ths ctxt
|
|
517 |
val head = hd iths |> strip_eq |> fst |> head_of
|
|
518 |
val eqs = map (strip_eq #> apfst (snd o strip_comb)) iths
|
|
519 |
|
|
520 |
fun hide_rhs ((pat, rhs), name) lthy =
|
|
521 |
let
|
|
522 |
val frees = fold Term.add_frees pat []
|
|
523 |
val abs_rhs = fold absfree frees rhs
|
|
524 |
val (f, def, lthy') = case lthy
|
|
525 |
|> Local_Defs.define [((Binding.name name, NoSyn), (Binding.empty_atts, abs_rhs))] of
|
|
526 |
([(f, (_, def))], lthy') => (f, def, lthy')
|
|
527 |
| _ => raise Match
|
|
528 |
in
|
|
529 |
((list_comb (f, map Free (rev frees)), def), lthy')
|
|
530 |
end
|
|
531 |
|
|
532 |
val rhs_names = Name.invent (Variable.names_of ctxt') "rhs" (length eqs)
|
|
533 |
val ((def_ts, def_thms), ctxt2) =
|
|
534 |
fold_map hide_rhs (eqs ~~ rhs_names) ctxt' |> apfst split_list
|
|
535 |
val (ts, split_thms, ctxt3) = build_case_t replace_ctr ctr_count head
|
|
536 |
(map fst eqs) def_ts ctxt2
|
|
537 |
fun mk_thm t = Goal.prove ctxt3 [] [] t
|
|
538 |
(fn {context=ctxt, ...} => tac ctxt {splits=split_thms, intros=ths, defs=def_thms} 1)
|
|
539 |
in
|
|
540 |
if null ts then NONE
|
|
541 |
else
|
|
542 |
ts
|
|
543 |
|> map mk_thm
|
|
544 |
|> Proof_Context.export ctxt3 ctxt
|
|
545 |
|> map (Goal.norm_result ctxt)
|
|
546 |
|> SOME
|
|
547 |
end;
|
|
548 |
|
|
549 |
end
|