moved src/Tools/Compute_Oracle to src/HOL/Matrix/Compute_Oracle -- it actually depends on HOL anyway;
(* Title: Tools/Compute_Oracle/compute.ML
Author: Steven Obua
*)
signature COMPUTE = sig
type computer
type theorem
type naming = int -> string
datatype machine = BARRAS | BARRAS_COMPILED | HASKELL | SML
(* Functions designated with a ! in front of them actually update the computer parameter *)
exception Make of string
val make : machine -> theory -> thm list -> computer
val make_with_cache : machine -> theory -> term list -> thm list -> computer
val theory_of : computer -> theory
val hyps_of : computer -> term list
val shyps_of : computer -> sort list
(* ! *) val update : computer -> thm list -> unit
(* ! *) val update_with_cache : computer -> term list -> thm list -> unit
(* ! *) val discard : computer -> unit
(* ! *) val set_naming : computer -> naming -> unit
val naming_of : computer -> naming
exception Compute of string
val simplify : computer -> theorem -> thm
val rewrite : computer -> cterm -> thm
val make_theorem : computer -> thm -> string list -> theorem
(* ! *) val instantiate : computer -> (string * cterm) list -> theorem -> theorem
(* ! *) val evaluate_prem : computer -> int -> theorem -> theorem
(* ! *) val modus_ponens : computer -> int -> thm -> theorem -> theorem
end
structure Compute :> COMPUTE = struct
open Report;
datatype machine = BARRAS | BARRAS_COMPILED | HASKELL | SML
(* Terms are mapped to integer codes *)
structure Encode :>
sig
type encoding
val empty : encoding
val insert : term -> encoding -> int * encoding
val lookup_code : term -> encoding -> int option
val lookup_term : int -> encoding -> term option
val remove_code : int -> encoding -> encoding
val remove_term : term -> encoding -> encoding
val fold : ((term * int) -> 'a -> 'a) -> encoding -> 'a -> 'a
end
=
struct
type encoding = int * (int Termtab.table) * (term Inttab.table)
val empty = (0, Termtab.empty, Inttab.empty)
fun insert t (e as (count, term2int, int2term)) =
(case Termtab.lookup term2int t of
NONE => (count, (count+1, Termtab.update_new (t, count) term2int, Inttab.update_new (count, t) int2term))
| SOME code => (code, e))
fun lookup_code t (_, term2int, _) = Termtab.lookup term2int t
fun lookup_term c (_, _, int2term) = Inttab.lookup int2term c
fun remove_code c (e as (count, term2int, int2term)) =
(case lookup_term c e of NONE => e | SOME t => (count, Termtab.delete t term2int, Inttab.delete c int2term))
fun remove_term t (e as (count, term2int, int2term)) =
(case lookup_code t e of NONE => e | SOME c => (count, Termtab.delete t term2int, Inttab.delete c int2term))
fun fold f (_, term2int, _) = Termtab.fold f term2int
end
exception Make of string;
exception Compute of string;
local
fun make_constant t ty encoding =
let
val (code, encoding) = Encode.insert t encoding
in
(encoding, AbstractMachine.Const code)
end
in
fun remove_types encoding t =
case t of
Var (_, ty) => make_constant t ty encoding
| Free (_, ty) => make_constant t ty encoding
| Const (_, ty) => make_constant t ty encoding
| Abs (_, ty, t') =>
let val (encoding, t'') = remove_types encoding t' in
(encoding, AbstractMachine.Abs t'')
end
| a $ b =>
let
val (encoding, a) = remove_types encoding a
val (encoding, b) = remove_types encoding b
in
(encoding, AbstractMachine.App (a,b))
end
| Bound b => (encoding, AbstractMachine.Var b)
end
local
fun type_of (Free (_, ty)) = ty
| type_of (Const (_, ty)) = ty
| type_of (Var (_, ty)) = ty
| type_of _ = sys_error "infer_types: type_of error"
in
fun infer_types naming encoding =
let
fun infer_types _ bounds _ (AbstractMachine.Var v) = (Bound v, List.nth (bounds, v))
| infer_types _ bounds _ (AbstractMachine.Const code) =
let
val c = the (Encode.lookup_term code encoding)
in
(c, type_of c)
end
| infer_types level bounds _ (AbstractMachine.App (a, b)) =
let
val (a, aty) = infer_types level bounds NONE a
val (adom, arange) =
case aty of
Type ("fun", [dom, range]) => (dom, range)
| _ => sys_error "infer_types: function type expected"
val (b, bty) = infer_types level bounds (SOME adom) b
in
(a $ b, arange)
end
| infer_types level bounds (SOME (ty as Type ("fun", [dom, range]))) (AbstractMachine.Abs m) =
let
val (m, _) = infer_types (level+1) (dom::bounds) (SOME range) m
in
(Abs (naming level, dom, m), ty)
end
| infer_types _ _ NONE (AbstractMachine.Abs m) = sys_error "infer_types: cannot infer type of abstraction"
fun infer ty term =
let
val (term', _) = infer_types 0 [] (SOME ty) term
in
term'
end
in
infer
end
end
datatype prog =
ProgBarras of AM_Interpreter.program
| ProgBarrasC of AM_Compiler.program
| ProgHaskell of AM_GHC.program
| ProgSML of AM_SML.program
fun machine_of_prog (ProgBarras _) = BARRAS
| machine_of_prog (ProgBarrasC _) = BARRAS_COMPILED
| machine_of_prog (ProgHaskell _) = HASKELL
| machine_of_prog (ProgSML _) = SML
type naming = int -> string
fun default_naming i = "v_" ^ Int.toString i
datatype computer = Computer of
(theory_ref * Encode.encoding * term list * unit Sorttab.table * prog * unit Unsynchronized.ref * naming)
option Unsynchronized.ref
fun theory_of (Computer (Unsynchronized.ref (SOME (rthy,_,_,_,_,_,_)))) = Theory.deref rthy
fun hyps_of (Computer (Unsynchronized.ref (SOME (_,_,hyps,_,_,_,_)))) = hyps
fun shyps_of (Computer (Unsynchronized.ref (SOME (_,_,_,shyptable,_,_,_)))) = Sorttab.keys (shyptable)
fun shyptab_of (Computer (Unsynchronized.ref (SOME (_,_,_,shyptable,_,_,_)))) = shyptable
fun stamp_of (Computer (Unsynchronized.ref (SOME (_,_,_,_,_,stamp,_)))) = stamp
fun prog_of (Computer (Unsynchronized.ref (SOME (_,_,_,_,prog,_,_)))) = prog
fun encoding_of (Computer (Unsynchronized.ref (SOME (_,encoding,_,_,_,_,_)))) = encoding
fun set_encoding (Computer (r as Unsynchronized.ref (SOME (p1,encoding,p2,p3,p4,p5,p6)))) encoding' =
(r := SOME (p1,encoding',p2,p3,p4,p5,p6))
fun naming_of (Computer (Unsynchronized.ref (SOME (_,_,_,_,_,_,n)))) = n
fun set_naming (Computer (r as Unsynchronized.ref (SOME (p1,p2,p3,p4,p5,p6,naming)))) naming'=
(r := SOME (p1,p2,p3,p4,p5,p6,naming'))
fun ref_of (Computer r) = r
datatype cthm = ComputeThm of term list * sort list * term
fun thm2cthm th =
let
val {hyps, prop, tpairs, shyps, ...} = Thm.rep_thm th
val _ = if not (null tpairs) then raise Make "theorems may not contain tpairs" else ()
in
ComputeThm (hyps, shyps, prop)
end
fun make_internal machine thy stamp encoding cache_pattern_terms raw_ths =
let
fun transfer (x:thm) = Thm.transfer thy x
val ths = map (thm2cthm o Thm.strip_shyps o transfer) raw_ths
fun make_pattern encoding n vars (var as AbstractMachine.Abs _) =
raise (Make "no lambda abstractions allowed in pattern")
| make_pattern encoding n vars (var as AbstractMachine.Var _) =
raise (Make "no bound variables allowed in pattern")
| make_pattern encoding n vars (AbstractMachine.Const code) =
(case the (Encode.lookup_term code encoding) of
Var _ => ((n+1, Inttab.update_new (code, n) vars, AbstractMachine.PVar)
handle Inttab.DUP _ => raise (Make "no duplicate variable in pattern allowed"))
| _ => (n, vars, AbstractMachine.PConst (code, [])))
| make_pattern encoding n vars (AbstractMachine.App (a, b)) =
let
val (n, vars, pa) = make_pattern encoding n vars a
val (n, vars, pb) = make_pattern encoding n vars b
in
case pa of
AbstractMachine.PVar =>
raise (Make "patterns may not start with a variable")
| AbstractMachine.PConst (c, args) =>
(n, vars, AbstractMachine.PConst (c, args@[pb]))
end
fun thm2rule (encoding, hyptable, shyptable) th =
let
val (ComputeThm (hyps, shyps, prop)) = th
val hyptable = fold (fn h => Termtab.update (h, ())) hyps hyptable
val shyptable = fold (fn sh => Sorttab.update (sh, ())) shyps shyptable
val (prems, prop) = (Logic.strip_imp_prems prop, Logic.strip_imp_concl prop)
val (a, b) = Logic.dest_equals prop
handle TERM _ => raise (Make "theorems must be meta-level equations (with optional guards)")
val a = Envir.eta_contract a
val b = Envir.eta_contract b
val prems = map Envir.eta_contract prems
val (encoding, left) = remove_types encoding a
val (encoding, right) = remove_types encoding b
fun remove_types_of_guard encoding g =
(let
val (t1, t2) = Logic.dest_equals g
val (encoding, t1) = remove_types encoding t1
val (encoding, t2) = remove_types encoding t2
in
(encoding, AbstractMachine.Guard (t1, t2))
end handle TERM _ => raise (Make "guards must be meta-level equations"))
val (encoding, prems) = fold_rev (fn p => fn (encoding, ps) => let val (e, p) = remove_types_of_guard encoding p in (e, p::ps) end) prems (encoding, [])
(* Principally, a check should be made here to see if the (meta-) hyps contain any of the variables of the rule.
As it is, all variables of the rule are schematic, and there are no schematic variables in meta-hyps, therefore
this check can be left out. *)
val (vcount, vars, pattern) = make_pattern encoding 0 Inttab.empty left
val _ = (case pattern of
AbstractMachine.PVar =>
raise (Make "patterns may not start with a variable")
(* | AbstractMachine.PConst (_, []) =>
(print th; raise (Make "no parameter rewrite found"))*)
| _ => ())
(* finally, provide a function for renaming the
pattern bound variables on the right hand side *)
fun rename level vars (var as AbstractMachine.Var _) = var
| rename level vars (c as AbstractMachine.Const code) =
(case Inttab.lookup vars code of
NONE => c
| SOME n => AbstractMachine.Var (vcount-n-1+level))
| rename level vars (AbstractMachine.App (a, b)) =
AbstractMachine.App (rename level vars a, rename level vars b)
| rename level vars (AbstractMachine.Abs m) =
AbstractMachine.Abs (rename (level+1) vars m)
fun rename_guard (AbstractMachine.Guard (a,b)) =
AbstractMachine.Guard (rename 0 vars a, rename 0 vars b)
in
((encoding, hyptable, shyptable), (map rename_guard prems, pattern, rename 0 vars right))
end
val ((encoding, hyptable, shyptable), rules) =
fold_rev (fn th => fn (encoding_hyptable, rules) =>
let
val (encoding_hyptable, rule) = thm2rule encoding_hyptable th
in (encoding_hyptable, rule::rules) end)
ths ((encoding, Termtab.empty, Sorttab.empty), [])
fun make_cache_pattern t (encoding, cache_patterns) =
let
val (encoding, a) = remove_types encoding t
val (_,_,p) = make_pattern encoding 0 Inttab.empty a
in
(encoding, p::cache_patterns)
end
val (encoding, cache_patterns) = fold_rev make_cache_pattern cache_pattern_terms (encoding, [])
fun arity (Type ("fun", [a,b])) = 1 + arity b
| arity _ = 0
fun make_arity (Const (s, _), i) tab =
(Inttab.update (i, arity (Sign.the_const_type thy s)) tab handle TYPE _ => tab)
| make_arity _ tab = tab
val const_arity_tab = Encode.fold make_arity encoding Inttab.empty
fun const_arity x = Inttab.lookup const_arity_tab x
val prog =
case machine of
BARRAS => ProgBarras (AM_Interpreter.compile cache_patterns const_arity rules)
| BARRAS_COMPILED => ProgBarrasC (AM_Compiler.compile cache_patterns const_arity rules)
| HASKELL => ProgHaskell (AM_GHC.compile cache_patterns const_arity rules)
| SML => ProgSML (AM_SML.compile cache_patterns const_arity rules)
fun has_witness s = not (null (Sign.witness_sorts thy [] [s]))
val shyptable = fold Sorttab.delete (filter has_witness (Sorttab.keys (shyptable))) shyptable
in (Theory.check_thy thy, encoding, Termtab.keys hyptable, shyptable, prog, stamp, default_naming) end
fun make_with_cache machine thy cache_patterns raw_thms =
Computer (Unsynchronized.ref (SOME (make_internal machine thy (Unsynchronized.ref ()) Encode.empty cache_patterns raw_thms)))
fun make machine thy raw_thms = make_with_cache machine thy [] raw_thms
fun update_with_cache computer cache_patterns raw_thms =
let
val c = make_internal (machine_of_prog (prog_of computer)) (theory_of computer) (stamp_of computer)
(encoding_of computer) cache_patterns raw_thms
val _ = (ref_of computer) := SOME c
in
()
end
fun update computer raw_thms = update_with_cache computer [] raw_thms
fun discard computer =
let
val _ =
case prog_of computer of
ProgBarras p => AM_Interpreter.discard p
| ProgBarrasC p => AM_Compiler.discard p
| ProgHaskell p => AM_GHC.discard p
| ProgSML p => AM_SML.discard p
val _ = (ref_of computer) := NONE
in
()
end
fun runprog (ProgBarras p) = AM_Interpreter.run p
| runprog (ProgBarrasC p) = AM_Compiler.run p
| runprog (ProgHaskell p) = AM_GHC.run p
| runprog (ProgSML p) = AM_SML.run p
(* ------------------------------------------------------------------------------------- *)
(* An oracle for exporting theorems; must only be accessible from inside this structure! *)
(* ------------------------------------------------------------------------------------- *)
fun merge_hyps hyps1 hyps2 =
let
fun add hyps tab = fold (fn h => fn tab => Termtab.update (h, ()) tab) hyps tab
in
Termtab.keys (add hyps2 (add hyps1 Termtab.empty))
end
fun add_shyps shyps tab = fold (fn h => fn tab => Sorttab.update (h, ()) tab) shyps tab
fun merge_shyps shyps1 shyps2 = Sorttab.keys (add_shyps shyps2 (add_shyps shyps1 Sorttab.empty))
val (_, export_oracle) = Context.>>> (Context.map_theory_result
(Thm.add_oracle (Binding.name "compute", fn (thy, hyps, shyps, prop) =>
let
val shyptab = add_shyps shyps Sorttab.empty
fun delete s shyptab = Sorttab.delete s shyptab handle Sorttab.UNDEF _ => shyptab
fun delete_term t shyptab = fold delete (Sorts.insert_term t []) shyptab
fun has_witness s = not (null (Sign.witness_sorts thy [] [s]))
val shyptab = fold Sorttab.delete (filter has_witness (Sorttab.keys (shyptab))) shyptab
val shyps = if Sorttab.is_empty shyptab then [] else Sorttab.keys (fold delete_term (prop::hyps) shyptab)
val _ =
if not (null shyps) then
raise Compute ("dangling sort hypotheses: " ^
commas (map (Syntax.string_of_sort_global thy) shyps))
else ()
in
Thm.cterm_of thy (fold_rev (fn hyp => fn p => Logic.mk_implies (hyp, p)) hyps prop)
end)));
fun export_thm thy hyps shyps prop =
let
val th = export_oracle (thy, hyps, shyps, prop)
val hyps = map (fn h => Thm.assume (cterm_of thy h)) hyps
in
fold (fn h => fn p => Thm.implies_elim p h) hyps th
end
(* --------- Rewrite ----------- *)
fun rewrite computer ct =
let
val thy = Thm.theory_of_cterm ct
val {t=t',T=ty,...} = rep_cterm ct
val _ = Theory.assert_super (theory_of computer) thy
val naming = naming_of computer
val (encoding, t) = remove_types (encoding_of computer) t'
(*val _ = if (!print_encoding) then writeln (makestring ("encoding: ",Encode.fold (fn x => fn s => x::s) encoding [])) else ()*)
val t = runprog (prog_of computer) t
val t = infer_types naming encoding ty t
val eq = Logic.mk_equals (t', t)
in
export_thm thy (hyps_of computer) (Sorttab.keys (shyptab_of computer)) eq
end
(* --------- Simplify ------------ *)
datatype prem = EqPrem of AbstractMachine.term * AbstractMachine.term * Term.typ * int
| Prem of AbstractMachine.term
datatype theorem = Theorem of theory_ref * unit Unsynchronized.ref * (int * typ) Symtab.table * (AbstractMachine.term option) Inttab.table
* prem list * AbstractMachine.term * term list * sort list
exception ParamSimplify of computer * theorem
fun make_theorem computer th vars =
let
val _ = Theory.assert_super (theory_of computer) (theory_of_thm th)
val (ComputeThm (hyps, shyps, prop)) = thm2cthm th
val encoding = encoding_of computer
(* variables in the theorem are identified upfront *)
fun collect_vars (Abs (_, _, t)) tab = collect_vars t tab
| collect_vars (a $ b) tab = collect_vars b (collect_vars a tab)
| collect_vars (Const _) tab = tab
| collect_vars (Free _) tab = tab
| collect_vars (Var ((s, i), ty)) tab =
if List.find (fn x => x=s) vars = NONE then
tab
else
(case Symtab.lookup tab s of
SOME ((s',i'),ty') =>
if s' <> s orelse i' <> i orelse ty <> ty' then
raise Compute ("make_theorem: variable name '"^s^"' is not unique")
else
tab
| NONE => Symtab.update (s, ((s, i), ty)) tab)
val vartab = collect_vars prop Symtab.empty
fun encodevar (s, t as (_, ty)) (encoding, tab) =
let
val (x, encoding) = Encode.insert (Var t) encoding
in
(encoding, Symtab.update (s, (x, ty)) tab)
end
val (encoding, vartab) = Symtab.fold encodevar vartab (encoding, Symtab.empty)
val varsubst = Inttab.make (map (fn (s, (x, _)) => (x, NONE)) (Symtab.dest vartab))
(* make the premises and the conclusion *)
fun mk_prem encoding t =
(let
val (a, b) = Logic.dest_equals t
val ty = type_of a
val (encoding, a) = remove_types encoding a
val (encoding, b) = remove_types encoding b
val (eq, encoding) = Encode.insert (Const ("==", ty --> ty --> @{typ "prop"})) encoding
in
(encoding, EqPrem (a, b, ty, eq))
end handle TERM _ => let val (encoding, t) = remove_types encoding t in (encoding, Prem t) end)
val (encoding, prems) =
(fold_rev (fn t => fn (encoding, l) =>
case mk_prem encoding t of
(encoding, t) => (encoding, t::l)) (Logic.strip_imp_prems prop) (encoding, []))
val (encoding, concl) = remove_types encoding (Logic.strip_imp_concl prop)
val _ = set_encoding computer encoding
in
Theorem (Theory.check_thy (theory_of_thm th), stamp_of computer, vartab, varsubst,
prems, concl, hyps, shyps)
end
fun theory_of_theorem (Theorem (rthy,_,_,_,_,_,_,_)) = Theory.deref rthy
fun update_theory thy (Theorem (_,p0,p1,p2,p3,p4,p5,p6)) =
Theorem (Theory.check_thy thy,p0,p1,p2,p3,p4,p5,p6)
fun stamp_of_theorem (Theorem (_,s, _, _, _, _, _, _)) = s
fun vartab_of_theorem (Theorem (_,_,vt,_,_,_,_,_)) = vt
fun varsubst_of_theorem (Theorem (_,_,_,vs,_,_,_,_)) = vs
fun update_varsubst vs (Theorem (p0,p1,p2,_,p3,p4,p5,p6)) = Theorem (p0,p1,p2,vs,p3,p4,p5,p6)
fun prems_of_theorem (Theorem (_,_,_,_,prems,_,_,_)) = prems
fun update_prems prems (Theorem (p0,p1,p2,p3,_,p4,p5,p6)) = Theorem (p0,p1,p2,p3,prems,p4,p5,p6)
fun concl_of_theorem (Theorem (_,_,_,_,_,concl,_,_)) = concl
fun hyps_of_theorem (Theorem (_,_,_,_,_,_,hyps,_)) = hyps
fun update_hyps hyps (Theorem (p0,p1,p2,p3,p4,p5,_,p6)) = Theorem (p0,p1,p2,p3,p4,p5,hyps,p6)
fun shyps_of_theorem (Theorem (_,_,_,_,_,_,_,shyps)) = shyps
fun update_shyps shyps (Theorem (p0,p1,p2,p3,p4,p5,p6,_)) = Theorem (p0,p1,p2,p3,p4,p5,p6,shyps)
fun check_compatible computer th s =
if stamp_of computer <> stamp_of_theorem th then
raise Compute (s^": computer and theorem are incompatible")
else ()
fun instantiate computer insts th =
let
val _ = check_compatible computer th
val thy = theory_of computer
val vartab = vartab_of_theorem th
fun rewrite computer t =
let
val naming = naming_of computer
val (encoding, t) = remove_types (encoding_of computer) t
val t = runprog (prog_of computer) t
val _ = set_encoding computer encoding
in
t
end
fun assert_varfree vs t =
if AbstractMachine.forall_consts (fn x => Inttab.lookup vs x = NONE) t then
()
else
raise Compute "instantiate: assert_varfree failed"
fun assert_closed t =
if AbstractMachine.closed t then
()
else
raise Compute "instantiate: not a closed term"
fun compute_inst (s, ct) vs =
let
val _ = Theory.assert_super (theory_of_cterm ct) thy
val ty = typ_of (ctyp_of_term ct)
in
(case Symtab.lookup vartab s of
NONE => raise Compute ("instantiate: variable '"^s^"' not found in theorem")
| SOME (x, ty') =>
(case Inttab.lookup vs x of
SOME (SOME _) => raise Compute ("instantiate: variable '"^s^"' has already been instantiated")
| SOME NONE =>
if ty <> ty' then
raise Compute ("instantiate: wrong type for variable '"^s^"'")
else
let
val t = rewrite computer (term_of ct)
val _ = assert_varfree vs t
val _ = assert_closed t
in
Inttab.update (x, SOME t) vs
end
| NONE => raise Compute "instantiate: internal error"))
end
val vs = fold compute_inst insts (varsubst_of_theorem th)
in
update_varsubst vs th
end
fun match_aterms subst =
let
exception no_match
open AbstractMachine
fun match subst (b as (Const c)) a =
if a = b then subst
else
(case Inttab.lookup subst c of
SOME (SOME a') => if a=a' then subst else raise no_match
| SOME NONE => if AbstractMachine.closed a then
Inttab.update (c, SOME a) subst
else raise no_match
| NONE => raise no_match)
| match subst (b as (Var _)) a = if a=b then subst else raise no_match
| match subst (App (u, v)) (App (u', v')) = match (match subst u u') v v'
| match subst (Abs u) (Abs u') = match subst u u'
| match subst _ _ = raise no_match
in
fn b => fn a => (SOME (match subst b a) handle no_match => NONE)
end
fun apply_subst vars_allowed subst =
let
open AbstractMachine
fun app (t as (Const c)) =
(case Inttab.lookup subst c of
NONE => t
| SOME (SOME t) => Computed t
| SOME NONE => if vars_allowed then t else raise Compute "apply_subst: no vars allowed")
| app (t as (Var _)) = t
| app (App (u, v)) = App (app u, app v)
| app (Abs m) = Abs (app m)
in
app
end
fun splicein n l L = List.take (L, n) @ l @ List.drop (L, n+1)
fun evaluate_prem computer prem_no th =
let
val _ = check_compatible computer th
val prems = prems_of_theorem th
val varsubst = varsubst_of_theorem th
fun run vars_allowed t =
runprog (prog_of computer) (apply_subst vars_allowed varsubst t)
in
case List.nth (prems, prem_no) of
Prem _ => raise Compute "evaluate_prem: no equality premise"
| EqPrem (a, b, ty, _) =>
let
val a' = run false a
val b' = run true b
in
case match_aterms varsubst b' a' of
NONE =>
let
fun mk s = Syntax.string_of_term_global Pure.thy
(infer_types (naming_of computer) (encoding_of computer) ty s)
val left = "computed left side: "^(mk a')
val right = "computed right side: "^(mk b')
in
raise Compute ("evaluate_prem: cannot assign computed left to right hand side\n"^left^"\n"^right^"\n")
end
| SOME varsubst =>
update_prems (splicein prem_no [] prems) (update_varsubst varsubst th)
end
end
fun prem2term (Prem t) = t
| prem2term (EqPrem (a,b,_,eq)) =
AbstractMachine.App (AbstractMachine.App (AbstractMachine.Const eq, a), b)
fun modus_ponens computer prem_no th' th =
let
val _ = check_compatible computer th
val thy =
let
val thy1 = theory_of_theorem th
val thy2 = theory_of_thm th'
in
if Theory.subthy (thy1, thy2) then thy2
else if Theory.subthy (thy2, thy1) then thy1 else
raise Compute "modus_ponens: theorems are not compatible with each other"
end
val th' = make_theorem computer th' []
val varsubst = varsubst_of_theorem th
fun run vars_allowed t =
runprog (prog_of computer) (apply_subst vars_allowed varsubst t)
val prems = prems_of_theorem th
val prem = run true (prem2term (List.nth (prems, prem_no)))
val concl = run false (concl_of_theorem th')
in
case match_aterms varsubst prem concl of
NONE => raise Compute "modus_ponens: conclusion does not match premise"
| SOME varsubst =>
let
val th = update_varsubst varsubst th
val th = update_prems (splicein prem_no (prems_of_theorem th') prems) th
val th = update_hyps (merge_hyps (hyps_of_theorem th) (hyps_of_theorem th')) th
val th = update_shyps (merge_shyps (shyps_of_theorem th) (shyps_of_theorem th')) th
in
update_theory thy th
end
end
fun simplify computer th =
let
val _ = check_compatible computer th
val varsubst = varsubst_of_theorem th
val encoding = encoding_of computer
val naming = naming_of computer
fun infer t = infer_types naming encoding @{typ "prop"} t
fun run t = infer (runprog (prog_of computer) (apply_subst true varsubst t))
fun runprem p = run (prem2term p)
val prop = Logic.list_implies (map runprem (prems_of_theorem th), run (concl_of_theorem th))
val hyps = merge_hyps (hyps_of computer) (hyps_of_theorem th)
val shyps = merge_shyps (shyps_of_theorem th) (Sorttab.keys (shyptab_of computer))
in
export_thm (theory_of_theorem th) hyps shyps prop
end
end