# HG changeset patch # User huffman # Date 1235675858 28800 # Node ID 243a05a67c4167eb1ddafb0f42f92c924c15f539 # Parent 6be1be402ef0c0196062efb83195ab7073069774 avoid using legacy type inference diff -r 6be1be402ef0 -r 243a05a67c41 src/HOLCF/Tools/fixrec_package.ML --- a/src/HOLCF/Tools/fixrec_package.ML Thu Feb 26 10:28:53 2009 -0800 +++ b/src/HOLCF/Tools/fixrec_package.ML Thu Feb 26 11:17:38 2009 -0800 @@ -8,6 +8,7 @@ sig val legacy_infer_term: theory -> term -> term val legacy_infer_prop: theory -> term -> term + val add_fixrec: bool -> (Attrib.binding * string) list list -> theory -> theory val add_fixrec_i: bool -> ((binding * attribute list) * term) list list -> theory -> theory val add_fixpat: Attrib.binding * string list -> theory -> theory @@ -20,7 +21,7 @@ struct (* legacy type inference *) - +(* used by the domain package *) fun legacy_infer_term thy t = singleton (Syntax.check_terms (ProofContext.init thy)) (Sign.intern_term thy t); @@ -35,15 +36,41 @@ fun fixrec_eq_err thy s eq = fixrec_err (s ^ "\nin\n" ^ quote (Syntax.string_of_term_global thy eq)); +(*************************************************************************) +(***************************** building types ****************************) +(*************************************************************************) + (* ->> is taken from holcf_logic.ML *) -(* TODO: fix dependencies so we can import HOLCFLogic here *) -infixr 6 ->>; -fun S ->> T = Type (@{type_name "->"},[S,T]); +fun cfunT (T, U) = Type(@{type_name "->"}, [T, U]); + +infixr 6 ->>; val (op ->>) = cfunT; + +fun dest_cfunT (Type(@{type_name "->"}, [T, U])) = (T, U) + | dest_cfunT T = raise TYPE ("dest_cfunT", [T], []); + +fun binder_cfun (Type(@{type_name "->"},[T, U])) = T :: binder_cfun U + | binder_cfun _ = []; + +fun body_cfun (Type(@{type_name "->"},[T, U])) = body_cfun U + | body_cfun T = T; -(* extern_name is taken from domain/library.ML *) -fun extern_name con = case Symbol.explode con of - ("o"::"p"::" "::rest) => implode rest - | _ => con; +fun strip_cfun T : typ list * typ = + (binder_cfun T, body_cfun T); + +fun maybeT T = Type(@{type_name "maybe"}, [T]); + +fun dest_maybeT (Type(@{type_name "maybe"}, [T])) = T + | dest_maybeT T = raise TYPE ("dest_maybeT", [T], []); + +fun tupleT [] = @{typ "unit"} + | tupleT [T] = T + | tupleT (T :: Ts) = HOLogic.mk_prodT (T, tupleT Ts); + +fun matchT T = body_cfun T ->> maybeT (tupleT (binder_cfun T)); + +(*************************************************************************) +(***************************** building terms ****************************) +(*************************************************************************) val mk_trp = HOLogic.mk_Trueprop; @@ -54,30 +81,86 @@ fun chead_of (Const(@{const_name Rep_CFun},_)$f$t) = chead_of f | chead_of u = u; -(* these are helpful functions copied from HOLCF/domain/library.ML *) -fun %: s = Free(s,dummyT); -fun %%: s = Const(s,dummyT); -infix 0 ==; fun S == T = %%:"==" $ S $ T; -infix 1 ===; fun S === T = %%:"op =" $ S $ T; -infix 9 ` ; fun f ` x = %%:@{const_name Rep_CFun} $ f $ x; +fun capply_const (S, T) = + Const(@{const_name Rep_CFun}, (S ->> T) --> (S --> T)); + +fun cabs_const (S, T) = + Const(@{const_name Abs_CFun}, (S --> T) --> (S ->> T)); + +fun mk_capply (t, u) = + let val (S, T) = + case Term.fastype_of t of + Type(@{type_name "->"}, [S, T]) => (S, T) + | _ => raise TERM ("mk_capply " ^ ML_Syntax.print_list ML_Syntax.print_term [t, u], [t, u]); + in capply_const (S, T) $ t $ u end; + +infix 0 ==; val (op ==) = Logic.mk_equals; +infix 1 ===; val (op ===) = HOLogic.mk_eq; +infix 9 ` ; val (op `) = mk_capply; + + +fun mk_cpair (t, u) = + let val T = Term.fastype_of t + val U = Term.fastype_of u + val cpairT = T ->> U ->> HOLogic.mk_prodT (T, U) + in Const(@{const_name cpair}, cpairT) ` t ` u end; + +fun mk_cfst t = + let val T = Term.fastype_of t; + val (U, _) = HOLogic.dest_prodT T; + in Const(@{const_name cfst}, T ->> U) ` t end; + +fun mk_csnd t = + let val T = Term.fastype_of t; + val (_, U) = HOLogic.dest_prodT T; + in Const(@{const_name csnd}, T ->> U) ` t end; + +fun mk_csplit t = + let val (S, TU) = dest_cfunT (Term.fastype_of t); + val (T, U) = dest_cfunT TU; + val csplitT = (S ->> T ->> U) ->> HOLogic.mk_prodT (S, T) ->> U; + in Const(@{const_name csplit}, csplitT) ` t end; (* builds the expression (LAM v. rhs) *) -fun big_lambda v rhs = %%:@{const_name Abs_CFun}$(Term.lambda v rhs); +fun big_lambda v rhs = + cabs_const (Term.fastype_of v, Term.fastype_of rhs) $ Term.lambda v rhs; (* builds the expression (LAM v1 v2 .. vn. rhs) *) fun big_lambdas [] rhs = rhs | big_lambdas (v::vs) rhs = big_lambda v (big_lambdas vs rhs); (* builds the expression (LAM . rhs) *) -fun lambda_ctuple [] rhs = big_lambda (%:"unit") rhs +fun lambda_ctuple [] rhs = big_lambda (Free("unit", HOLogic.unitT)) rhs | lambda_ctuple (v::[]) rhs = big_lambda v rhs | lambda_ctuple (v::vs) rhs = - %%:@{const_name csplit}`(big_lambda v (lambda_ctuple vs rhs)); + mk_csplit (big_lambda v (lambda_ctuple vs rhs)); (* builds the expression *) -fun mk_ctuple [] = %%:"UU" +fun mk_ctuple [] = @{term "UU::unit"} | mk_ctuple (t::[]) = t -| mk_ctuple (t::ts) = %%:@{const_name cpair}`t`(mk_ctuple ts); +| mk_ctuple (t::ts) = mk_cpair (t, mk_ctuple ts); + +fun mk_return t = + let val T = Term.fastype_of t + in Const(@{const_name Fixrec.return}, T ->> maybeT T) ` t end; + +fun mk_bind (t, u) = + let val (T, mU) = dest_cfunT (Term.fastype_of u); + val bindT = maybeT T ->> (T ->> mU) ->> mU; + in Const(@{const_name Fixrec.bind}, bindT) ` t ` u end; + +fun mk_mplus (t, u) = + let val mT = Term.fastype_of t + in Const(@{const_name Fixrec.mplus}, mT ->> mT ->> mT) ` t ` u end; + +fun mk_run t = + let val mT = Term.fastype_of t + val T = dest_maybeT mT + in Const(@{const_name Fixrec.run}, mT ->> T) ` t end; + +fun mk_fix t = + let val (T, _) = dest_cfunT (Term.fastype_of t) + in Const(@{const_name fix}, (T ->> T) ->> T) ` t end; (*************************************************************************) (************* fixed-point definitions and unfolding theorems ************) @@ -86,22 +169,21 @@ fun add_fixdefs eqs thy = let val (lhss,rhss) = ListPair.unzip (map dest_eqs eqs); - val fixpoint = %%:@{const_name fix}`lambda_ctuple lhss (mk_ctuple rhss); + val fixpoint = mk_fix (lambda_ctuple lhss (mk_ctuple rhss)); fun one_def (l as Const(n,T)) r = let val b = Sign.base_name n in (b, (b^"_def", l == r)) end | one_def _ _ = fixrec_err "fixdefs: lhs not of correct form"; fun defs [] _ = [] | defs (l::[]) r = [one_def l r] - | defs (l::ls) r = one_def l (%%:@{const_name cfst}`r) :: defs ls (%%:@{const_name csnd}`r); - val (names, pre_fixdefs) = ListPair.unzip (defs lhss fixpoint); + | defs (l::ls) r = one_def l (mk_cfst r) :: defs ls (mk_csnd r); + val (names, fixdefs) = ListPair.unzip (defs lhss fixpoint); - val fixdefs = map (apsnd (legacy_infer_prop thy)) pre_fixdefs; val (fixdef_thms, thy') = PureThy.add_defs false (map (Thm.no_attributes o apfst Binding.name) fixdefs) thy; val ctuple_fixdef_thm = foldr1 (fn (x,y) => @{thm cpair_equalI} OF [x,y]) fixdef_thms; - val ctuple_unfold = legacy_infer_term thy' (mk_trp (mk_ctuple lhss === mk_ctuple rhss)); + val ctuple_unfold = mk_trp (mk_ctuple lhss === mk_ctuple rhss); val ctuple_unfold_thm = Goal.prove_global thy' [] [] ctuple_unfold (fn _ => EVERY [rtac (ctuple_fixdef_thm RS fix_eq2 RS trans) 1, simp_tac (simpset_of thy') 1]); @@ -158,10 +240,10 @@ fun result_type (Type(@{type_name "->"},[_,T])) (x::xs) = result_type T xs | result_type T _ = T; val v = Free(n, result_type T vs); - val m = match_name c; + val m = Const(match_name c, matchT T); val k = lambda_ctuple vs rhs; in - (%%:@{const_name Fixrec.bind}`(%%:m`v)`k, v, n::taken) + (mk_bind (m`v, k), v, n::taken) end | Free(n,_) => fixrec_err ("expected constructor, found free variable " ^ quote n) | _ => fixrec_err "pre_build: invalid pattern"; @@ -175,13 +257,13 @@ | Const(@{const_name Rep_CFun}, _)$f$x => let val (rhs', v, taken') = pre_build match_name x rhs [] taken; in building match_name f rhs' (v::vs) taken' end - | Const(name,_) => (name, length vs, big_lambdas vs rhs) + | Const(name,_) => (pat, length vs, big_lambdas vs rhs) | _ => fixrec_err "function is not declared as constant in theory"; fun match_eq match_name eq = let val (lhs,rhs) = dest_eqs eq; in - building match_name lhs (%%:@{const_name Fixrec.return}`rhs) [] + building match_name lhs (mk_return rhs) [] (add_terms [eq] []) end; @@ -189,15 +271,19 @@ (* also applies "run" to the result! *) fun fatbar arity ms = let + fun LAM_Ts 0 t = ([], Term.fastype_of t) + | LAM_Ts n (_ $ Abs(_,T,t)) = + let val (Ts, U) = LAM_Ts (n-1) t in (T::Ts, U) end + | LAM_Ts _ _ = fixrec_err "fatbar: internal error, not enough LAMs"; fun unLAM 0 t = t | unLAM n (_$Abs(_,_,t)) = unLAM (n-1) t | unLAM _ _ = fixrec_err "fatbar: internal error, not enough LAMs"; - fun reLAM 0 t = t - | reLAM n t = reLAM (n-1) (%%:@{const_name Abs_CFun} $ Abs("",dummyT,t)); - fun mplus (x,y) = %%:@{const_name Fixrec.mplus}`x`y; - val msum = foldr1 mplus (map (unLAM arity) ms); + fun reLAM ([], U) t = t + | reLAM (T::Ts, U) t = reLAM (Ts, T ->> U) (cabs_const(T,U)$Abs("",T,t)); + val msum = foldr1 mk_mplus (map (unLAM arity) ms); + val (Ts, U) = LAM_Ts arity (hd ms) in - reLAM arity (%%:@{const_name Fixrec.run}`msum) + reLAM (rev Ts, dest_maybeT U) (mk_run msum) end; fun unzip3 [] = ([],[],[]) @@ -215,7 +301,7 @@ else fixrec_err "all equations in block must have the same arity"; val rhs = fatbar arity mats; in - mk_trp (%%:cname === rhs) + mk_trp (cname === rhs) end; (*************************************************************************) @@ -258,7 +344,7 @@ val pattern_blocks = unconcat lengths (map Logic.strip_imp_concl eqn_ts'); val compiled_ts = - map (legacy_infer_term thy o compile_pats match_name) pattern_blocks; + map (compile_pats match_name) pattern_blocks; val (thy', cnames, fixdef_thms, unfold_thms) = add_fixdefs compiled_ts thy; in if strict then let (* only prove simp rules if strict = true *)