author | wenzelm |
Sat, 02 Apr 2016 23:29:05 +0200 | |
changeset 62826 | eb94e570c1a4 |
parent 61413 | 6d892287d0e9 |
child 63265 | 9a2377b96ffd |
permissions | -rw-r--r-- |
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(* Title: Provers/blast.ML |
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Author: Lawrence C Paulson, Cambridge University Computer Laboratory |
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Copyright 1997 University of Cambridge |
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Generic tableau prover with proof reconstruction |
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SKOLEMIZES ReplaceI WRONGLY: allow new vars in prems, or forbid such rules?? |
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Needs explicit instantiation of assumptions? |
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Given the typeargs system, constructor Const could be eliminated, with |
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TConst replaced by a constructor that takes the typargs list as an argument. |
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However, Const is heavily used for logical connectives. |
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Blast_tac is often more powerful than fast_tac, but has some limitations. |
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Blast_tac... |
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* ignores wrappers (addss, addbefore, addafter, addWrapper, ...); |
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this restriction is intrinsic |
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* ignores elimination rules that don't have the correct format |
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(conclusion must be a formula variable) |
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* rules must not require higher-order unification, e.g. apply_type in ZF |
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+ message "Function unknown's argument not a bound variable" relates to this |
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* its proof strategy is more general but can actually be slower |
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Known problems: |
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"Recursive" chains of rules can sometimes exclude other unsafe formulae |
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from expansion. This happens because newly-created formulae always |
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have priority over existing ones. But obviously recursive rules |
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such as transitivity are treated specially to prevent this. Sometimes |
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the formulae get into the wrong order (see WRONG below). |
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Loop detection: before expanding a haz formula, see whether it is a duplicate
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With substition for equalities (hyp_subst_tac): |
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When substitution affects an unsage formula or literal, it is moved |
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back to the list of safe formulae. |
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But there's no way of putting it in the right place. A "moved" or |
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"no DETERM" flag would prevent proofs failing here. |
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*) |
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signature BLAST_DATA = |
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sig |
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structure Classical: CLASSICAL |
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val Trueprop_const: string * typ |
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val equality_name: string |
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val not_name: string |
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val notE: thm (* [| ~P; P |] ==> R *) |
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val ccontr: thm |
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val hyp_subst_tac: Proof.context -> bool -> int -> tactic |
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end; |
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signature BLAST = |
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sig |
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exception TRANS of string (*reports translation errors*) |
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datatype term = |
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Const of string * term list |
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| Skolem of string * term option Unsynchronized.ref list |
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| Free of string |
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| Var of term option Unsynchronized.ref |
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| Bound of int |
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| Abs of string*term |
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| $ of term*term; |
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val depth_tac: Proof.context -> int -> int -> tactic |
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val depth_limit: int Config.T |
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val trace: bool Config.T |
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val stats: bool Config.T |
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val blast_tac: Proof.context -> int -> tactic |
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(*debugging tools*) |
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type branch |
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val tryIt: Proof.context -> int -> string -> |
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{fullTrace: branch list list, |
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result: ((int -> tactic) list * branch list list * (int * int * exn) list)} |
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end; |
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functor Blast(Data: BLAST_DATA): BLAST = |
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struct |
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structure Classical = Data.Classical; |
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(* options *) |
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val depth_limit = Attrib.setup_config_int @{binding blast_depth_limit} (K 20); |
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val (trace, _) = Attrib.config_bool @{binding blast_trace} (K false); |
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val (stats, _) = Attrib.config_bool @{binding blast_stats} (K false); |
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datatype term = |
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Const of string * term list (*typargs constant--as a terms!*) |
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| Skolem of string * term option Unsynchronized.ref list |
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| Free of string |
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| Var of term option Unsynchronized.ref |
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| Bound of int |
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| Abs of string*term |
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| op $ of term*term; |
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(*Pending formulae carry md (may duplicate) flags*) |
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type branch = |
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{pairs: ((term*bool) list * (*safe formulae on this level*) |
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(term*bool) list) list, (*unsafe formulae on this level*) |
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lits: term list, (*literals: irreducible formulae*) |
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vars: term option Unsynchronized.ref list, (*variables occurring in branch*) |
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lim: int}; (*resource limit*) |
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(* global state information *) |
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datatype state = State of |
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{ctxt: Proof.context, |
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names: Name.context Unsynchronized.ref, |
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fullTrace: branch list list Unsynchronized.ref, |
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trail: term option Unsynchronized.ref list Unsynchronized.ref, |
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ntrail: int Unsynchronized.ref, |
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nclosed: int Unsynchronized.ref, |
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ntried: int Unsynchronized.ref} |
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fun reject_const thy c = |
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is_some (Sign.const_type thy c) andalso |
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error ("blast: theory contains illegal constant " ^ quote c); |
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fun initialize ctxt = |
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let |
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val thy = Proof_Context.theory_of ctxt; |
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val _ = reject_const thy "*Goal*"; |
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val _ = reject_const thy "*False*"; |
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in |
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State |
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{ctxt = ctxt, |
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names = Unsynchronized.ref (Variable.names_of ctxt), |
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fullTrace = Unsynchronized.ref [], |
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trail = Unsynchronized.ref [], |
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ntrail = Unsynchronized.ref 0, |
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nclosed = Unsynchronized.ref 0, (*number of branches closed during the search*) |
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ntried = Unsynchronized.ref 1} (*number of branches created by splitting (counting from 1)*) |
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end; |
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fun gensym (State {names, ...}) x = |
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Unsynchronized.change_result names (Name.variant x); |
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(** Basic syntactic operations **) |
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fun is_Var (Var _) = true |
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| is_Var _ = false; |
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fun dest_Var (Var x) = x; |
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fun rand (f$x) = x; |
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(* maps (f, [t1,...,tn]) to f(t1,...,tn) *) |
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val list_comb : term * term list -> term = Library.foldl (op $); |
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(* maps f(t1,...,tn) to (f, [t1,...,tn]) ; naturally tail-recursive*) |
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fun strip_comb u : term * term list = |
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let fun stripc (f$t, ts) = stripc (f, t::ts) |
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| stripc x = x |
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in stripc(u,[]) end; |
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(* maps f(t1,...,tn) to f , which is never a combination *) |
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fun head_of (f$t) = head_of f |
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| head_of u = u; |
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(** Particular constants **) |
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fun negate P = Const (Data.not_name, []) $ P; |
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fun isNot (Const (c, _) $ _) = c = Data.not_name |
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| isNot _ = false; |
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fun mkGoal P = Const ("*Goal*", []) $ P; |
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fun isGoal (Const ("*Goal*", _) $ _) = true |
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| isGoal _ = false; |
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val (TruepropC, TruepropT) = Data.Trueprop_const; |
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fun mk_Trueprop t = Term.$ (Term.Const (TruepropC, TruepropT), t); |
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fun strip_Trueprop (tm as Const (c, _) $ t) = if c = TruepropC then t else tm |
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| strip_Trueprop tm = tm; |
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(*** Dealing with overloaded constants ***) |
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(*alist is a map from TVar names to Vars. We need to unify the TVars |
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faithfully in order to track overloading*) |
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fun fromType alist (Term.Type(a,Ts)) = list_comb (Const (a, []), map (fromType alist) Ts) |
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| fromType alist (Term.TFree(a,_)) = Free a |
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| fromType alist (Term.TVar (ixn,_)) = |
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(case (AList.lookup (op =) (!alist) ixn) of |
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NONE => let val t' = Var (Unsynchronized.ref NONE) |
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in alist := (ixn, t') :: !alist; t' |
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end |
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| SOME v => v) |
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fun fromConst thy alist (a, T) = |
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Const (a, map (fromType alist) (Sign.const_typargs thy (a, T))); |
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(*Tests whether 2 terms are alpha-convertible; chases instantiations*) |
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fun (Const (a, ts)) aconv (Const (b, us)) = a = b andalso aconvs (ts, us) |
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| (Skolem (a,_)) aconv (Skolem (b,_)) = a = b (*arglists must then be equal*) |
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| (Free a) aconv (Free b) = a = b |
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| (Var (Unsynchronized.ref(SOME t))) aconv u = t aconv u |
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| t aconv (Var (Unsynchronized.ref (SOME u))) = t aconv u |
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| (Var v) aconv (Var w) = v=w (*both Vars are un-assigned*) |
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| (Bound i) aconv (Bound j) = i=j |
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| (Abs(_,t)) aconv (Abs(_,u)) = t aconv u |
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| (f$t) aconv (g$u) = (f aconv g) andalso (t aconv u) |
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| _ aconv _ = false |
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and aconvs ([], []) = true |
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| aconvs (t :: ts, u :: us) = t aconv u andalso aconvs (ts, us) |
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| aconvs _ = false; |
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fun mem_term (_, []) = false |
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| mem_term (t, t'::ts) = t aconv t' orelse mem_term(t,ts); |
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fun ins_term(t,ts) = if mem_term(t,ts) then ts else t :: ts; |
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fun mem_var (v: term option Unsynchronized.ref, []) = false |
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| mem_var (v, v'::vs) = v=v' orelse mem_var(v,vs); |
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222 |
fun ins_var(v,vs) = if mem_var(v,vs) then vs else v :: vs; |
|
223 |
||
224 |
||
225 |
(** Vars **) |
|
226 |
||
227 |
(*Accumulates the Vars in the term, suppressing duplicates*) |
|
32740 | 228 |
fun add_term_vars (Skolem(a,args), vars) = add_vars_vars(args,vars) |
229 |
| add_term_vars (Var (v as Unsynchronized.ref NONE), vars) = ins_var (v, vars) |
|
230 |
| add_term_vars (Var (Unsynchronized.ref (SOME u)), vars) = add_term_vars (u, vars) |
|
231 |
| add_term_vars (Const (_, ts), vars) = add_terms_vars (ts, vars) |
|
232 |
| add_term_vars (Abs (_, body), vars) = add_term_vars (body, vars) |
|
233 |
| add_term_vars (f $ t, vars) = add_term_vars (f, add_term_vars (t, vars)) |
|
234 |
| add_term_vars (_, vars) = vars |
|
2854 | 235 |
(*Term list version. [The fold functionals are slow]*) |
236 |
and add_terms_vars ([], vars) = vars |
|
237 |
| add_terms_vars (t::ts, vars) = add_terms_vars (ts, add_term_vars(t,vars)) |
|
238 |
(*Var list version.*) |
|
32740 | 239 |
and add_vars_vars ([], vars) = vars |
240 |
| add_vars_vars (Unsynchronized.ref (SOME u) :: vs, vars) = |
|
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add_vars_vars (vs, add_term_vars(u,vars)) |
15531 | 242 |
| add_vars_vars (v::vs, vars) = (*v must be a ref NONE*) |
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243 |
add_vars_vars (vs, ins_var (v, vars)); |
2854 | 244 |
|
245 |
||
246 |
(*Chase assignments in "vars"; return a list of unassigned variables*) |
|
247 |
fun vars_in_vars vars = add_vars_vars(vars,[]); |
|
248 |
||
249 |
||
250 |
||
251 |
(*increment a term's non-local bound variables |
|
252 |
inc is increment for bound variables |
|
253 |
lev is level at which a bound variable is considered 'loose'*) |
|
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fun incr_bv (inc, lev, u as Bound i) = if i>=lev then Bound(i+inc) else u |
2854 | 255 |
| incr_bv (inc, lev, Abs(a,body)) = Abs(a, incr_bv(inc,lev+1,body)) |
256 |
| incr_bv (inc, lev, f$t) = incr_bv(inc,lev,f) $ incr_bv(inc,lev,t) |
|
257 |
| incr_bv (inc, lev, u) = u; |
|
258 |
||
259 |
fun incr_boundvars 0 t = t |
|
260 |
| incr_boundvars inc t = incr_bv(inc,0,t); |
|
261 |
||
262 |
||
263 |
(*Accumulate all 'loose' bound vars referring to level 'lev' or beyond. |
|
264 |
(Bound 0) is loose at level 0 *) |
|
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265 |
fun add_loose_bnos (Bound i, lev, js) = if i<lev then js |
20854 | 266 |
else insert (op =) (i - lev) js |
2854 | 267 |
| add_loose_bnos (Abs (_,t), lev, js) = add_loose_bnos (t, lev+1, js) |
268 |
| add_loose_bnos (f$t, lev, js) = |
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269 |
add_loose_bnos (f, lev, add_loose_bnos (t, lev, js)) |
2854 | 270 |
| add_loose_bnos (_, _, js) = js; |
271 |
||
272 |
fun loose_bnos t = add_loose_bnos (t, 0, []); |
|
273 |
||
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274 |
fun subst_bound (arg, t) : term = |
2854 | 275 |
let fun subst (t as Bound i, lev) = |
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276 |
if i<lev then t (*var is locally bound*) |
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277 |
else if i=lev then incr_boundvars lev arg |
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278 |
else Bound(i-1) (*loose: change it*) |
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279 |
| subst (Abs(a,body), lev) = Abs(a, subst(body,lev+1)) |
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280 |
| subst (f$t, lev) = subst(f,lev) $ subst(t,lev) |
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281 |
| subst (t,lev) = t |
2854 | 282 |
in subst (t,0) end; |
283 |
||
284 |
||
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285 |
(*Normalize...but not the bodies of ABSTRACTIONS*) |
2854 | 286 |
fun norm t = case t of |
32740 | 287 |
Skolem (a, args) => Skolem (a, vars_in_vars args) |
288 |
| Const (a, ts) => Const (a, map norm ts) |
|
289 |
| (Var (Unsynchronized.ref NONE)) => t |
|
290 |
| (Var (Unsynchronized.ref (SOME u))) => norm u |
|
2854 | 291 |
| (f $ u) => (case norm f of |
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292 |
Abs(_,body) => norm (subst_bound (u, body)) |
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293 |
| nf => nf $ norm u) |
2854 | 294 |
| _ => t; |
295 |
||
296 |
||
297 |
(*Weak (one-level) normalize for use in unification*) |
|
298 |
fun wkNormAux t = case t of |
|
299 |
(Var v) => (case !v of |
|
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300 |
SOME u => wkNorm u |
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301 |
| NONE => t) |
2854 | 302 |
| (f $ u) => (case wkNormAux f of |
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303 |
Abs(_,body) => wkNorm (subst_bound (u, body)) |
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304 |
| nf => nf $ u) |
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305 |
| Abs (a,body) => (*eta-contract if possible*) |
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306 |
(case wkNormAux body of |
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307 |
nb as (f $ t) => |
20664 | 308 |
if member (op =) (loose_bnos f) 0 orelse wkNorm t <> Bound 0 |
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309 |
then Abs(a,nb) |
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310 |
else wkNorm (incr_boundvars ~1 f) |
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311 |
| nb => Abs (a,nb)) |
2854 | 312 |
| _ => t |
313 |
and wkNorm t = case head_of t of |
|
314 |
Const _ => t |
|
315 |
| Skolem(a,args) => t |
|
316 |
| Free _ => t |
|
317 |
| _ => wkNormAux t; |
|
318 |
||
319 |
||
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320 |
(*Does variable v occur in u? For unification. |
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|
321 |
Dangling bound vars are also forbidden.*) |
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322 |
fun varOccur v = |
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323 |
let fun occL lev [] = false (*same as (exists occ), but faster*) |
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324 |
| occL lev (u::us) = occ lev u orelse occL lev us |
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|
325 |
and occ lev (Var w) = |
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|
326 |
v=w orelse |
15531 | 327 |
(case !w of NONE => false |
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328 |
| SOME u => occ lev u) |
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|
329 |
| occ lev (Skolem(_,args)) = occL lev (map Var args) |
18177 | 330 |
(*ignore Const, since term variables can't occur in types (?) *) |
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|
331 |
| occ lev (Bound i) = lev <= i |
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|
332 |
| occ lev (Abs(_,u)) = occ (lev+1) u |
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|
333 |
| occ lev (f$u) = occ lev u orelse occ lev f |
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|
334 |
| occ lev _ = false; |
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|
335 |
in occ 0 end; |
2854 | 336 |
|
337 |
exception UNIFY; |
|
338 |
||
339 |
||
340 |
(*Restore the trail to some previous state: for backtracking*) |
|
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|
341 |
fun clearTo (State {ntrail, trail, ...}) n = |
3083 | 342 |
while !ntrail<>n do |
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|
343 |
(hd(!trail) := NONE; |
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|
344 |
trail := tl (!trail); |
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|
345 |
ntrail := !ntrail - 1); |
2854 | 346 |
|
347 |
||
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348 |
(*First-order unification with bound variables. |
2854 | 349 |
"vars" is a list of variables local to the rule and NOT to be put |
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|
350 |
on the trail (no point in doing so) |
2854 | 351 |
*) |
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|
352 |
fun unify state (vars,t,u) = |
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|
353 |
let val State {ntrail, trail, ...} = state |
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|
354 |
val n = !ntrail |
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|
355 |
fun update (t as Var v, u) = |
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|
356 |
if t aconv u then () |
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|
357 |
else if varOccur v u then raise UNIFY |
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|
358 |
else if mem_var(v, vars) then v := SOME u |
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|
359 |
else (*avoid updating Vars in the branch if possible!*) |
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|
360 |
if is_Var u andalso mem_var(dest_Var u, vars) |
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|
361 |
then dest_Var u := SOME t |
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|
362 |
else (v := SOME u; |
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|
363 |
trail := v :: !trail; ntrail := !ntrail + 1) |
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|
364 |
fun unifyAux (t,u) = |
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|
365 |
case (wkNorm t, wkNorm u) of |
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|
366 |
(nt as Var v, nu) => update(nt,nu) |
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|
367 |
| (nu, nt as Var v) => update(nt,nu) |
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|
368 |
| (Const(a,ats), Const(b,bts)) => if a=b then unifysAux(ats,bts) |
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|
369 |
else raise UNIFY |
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|
370 |
| (Abs(_,t'), Abs(_,u')) => unifyAux(t',u') |
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|
371 |
(*NB: can yield unifiers having dangling Bound vars!*) |
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|
372 |
| (f$t', g$u') => (unifyAux(f,g); unifyAux(t',u')) |
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|
373 |
| (nt, nu) => if nt aconv nu then () else raise UNIFY |
18177 | 374 |
and unifysAux ([], []) = () |
375 |
| unifysAux (t :: ts, u :: us) = (unifyAux (t, u); unifysAux (ts, us)) |
|
376 |
| unifysAux _ = raise UNIFY; |
|
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|
377 |
in (unifyAux(t,u); true) handle UNIFY => (clearTo state n; false) |
2854 | 378 |
end; |
379 |
||
380 |
||
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|
381 |
(*Convert from "real" terms to prototerms; eta-contract. |
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|
382 |
Code is similar to fromSubgoal.*) |
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|
383 |
fun fromTerm thy t = |
32740 | 384 |
let val alistVar = Unsynchronized.ref [] |
385 |
and alistTVar = Unsynchronized.ref [] |
|
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|
386 |
fun from (Term.Const aT) = fromConst thy alistTVar aT |
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|
387 |
| from (Term.Free (a,_)) = Free a |
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|
388 |
| from (Term.Bound i) = Bound i |
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|
389 |
| from (Term.Var (ixn,T)) = |
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|
390 |
(case (AList.lookup (op =) (!alistVar) ixn) of |
32740 | 391 |
NONE => let val t' = Var (Unsynchronized.ref NONE) |
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|
392 |
in alistVar := (ixn, t') :: !alistVar; t' |
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|
393 |
end |
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|
394 |
| SOME v => v) |
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|
395 |
| from (Term.Abs (a,_,u)) = |
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|
396 |
(case from u of |
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|
397 |
u' as (f $ Bound 0) => |
20664 | 398 |
if member (op =) (loose_bnos f) 0 then Abs(a,u') |
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|
399 |
else incr_boundvars ~1 f |
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|
400 |
| u' => Abs(a,u')) |
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|
401 |
| from (Term.$ (f,u)) = from f $ from u |
2854 | 402 |
in from t end; |
403 |
||
4065 | 404 |
(*A debugging function: replaces all Vars by dummy Frees for visual inspection |
405 |
of whether they are distinct. Function revert undoes the assignments.*) |
|
406 |
fun instVars t = |
|
32740 | 407 |
let val name = Unsynchronized.ref "a" |
408 |
val updated = Unsynchronized.ref [] |
|
18177 | 409 |
fun inst (Const(a,ts)) = List.app inst ts |
32740 | 410 |
| inst (Var(v as Unsynchronized.ref NONE)) = (updated := v :: (!updated); |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
411 |
v := SOME (Free ("?" ^ !name)); |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
412 |
name := Symbol.bump_string (!name)) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
413 |
| inst (Abs(a,t)) = inst t |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
414 |
| inst (f $ u) = (inst f; inst u) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
415 |
| inst _ = () |
15570 | 416 |
fun revert() = List.app (fn v => v:=NONE) (!updated) |
4065 | 417 |
in inst t; revert end; |
418 |
||
419 |
||
2854 | 420 |
(* A1==>...An==>B goes to [A1,...,An], where B is not an implication *) |
56245 | 421 |
fun strip_imp_prems (Const (@{const_name Pure.imp}, _) $ A $ B) = |
422 |
strip_Trueprop A :: strip_imp_prems B |
|
2854 | 423 |
| strip_imp_prems _ = []; |
424 |
||
425 |
(* A1==>...An==>B goes to B, where B is not an implication *) |
|
56245 | 426 |
fun strip_imp_concl (Const (@{const_name Pure.imp}, _) $ A $ B) = strip_imp_concl B |
18177 | 427 |
| strip_imp_concl A = strip_Trueprop A; |
428 |
||
2854 | 429 |
|
430 |
||
431 |
(*** Conversion of Elimination Rules to Tableau Operations ***) |
|
432 |
||
9170 | 433 |
exception ElimBadConcl and ElimBadPrem; |
434 |
||
435 |
(*The conclusion becomes the goal/negated assumption *False*: delete it! |
|
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
436 |
If we don't find it then the premise is ill-formed and could cause |
9170 | 437 |
PROOF FAILED*) |
438 |
fun delete_concl [] = raise ElimBadPrem |
|
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
439 |
| delete_concl (P :: Ps) = |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
440 |
(case P of |
32740 | 441 |
Const (c, _) $ Var (Unsynchronized.ref (SOME (Const ("*False*", _)))) => |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
442 |
if c = "*Goal*" orelse c = Data.not_name then Ps |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
443 |
else P :: delete_concl Ps |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
444 |
| _ => P :: delete_concl Ps); |
2854 | 445 |
|
56245 | 446 |
fun skoPrem state vars (Const (@{const_name Pure.all}, _) $ Abs (_, P)) = |
43349 | 447 |
skoPrem state vars (subst_bound (Skolem (gensym state "S", vars), P)) |
448 |
| skoPrem _ _ P = P; |
|
2854 | 449 |
|
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
450 |
fun convertPrem t = |
9170 | 451 |
delete_concl (mkGoal (strip_imp_concl t) :: strip_imp_prems t); |
2854 | 452 |
|
453 |
(*Expects elimination rules to have a formula variable as conclusion*) |
|
43349 | 454 |
fun convertRule state vars t = |
2854 | 455 |
let val (P::Ps) = strip_imp_prems t |
456 |
val Var v = strip_imp_concl t |
|
18177 | 457 |
in v := SOME (Const ("*False*", [])); |
43349 | 458 |
(P, map (convertPrem o skoPrem state vars) Ps) |
9170 | 459 |
end |
460 |
handle Bind => raise ElimBadConcl; |
|
2854 | 461 |
|
462 |
||
463 |
(*Like dup_elim, but puts the duplicated major premise FIRST*) |
|
58958 | 464 |
fun rev_dup_elim ctxt th = (th RSN (2, revcut_rl)) |> Thm.assumption (SOME ctxt) 2 |> Seq.hd; |
2854 | 465 |
|
466 |
||
4391
cc3e8453d7f0
More deterministic and therefore faster (sometimes) proof reconstruction
paulson
parents:
4354
diff
changeset
|
467 |
(*Rotate the assumptions in all new subgoals for the LIFO discipline*) |
cc3e8453d7f0
More deterministic and therefore faster (sometimes) proof reconstruction
paulson
parents:
4354
diff
changeset
|
468 |
local |
cc3e8453d7f0
More deterministic and therefore faster (sometimes) proof reconstruction
paulson
parents:
4354
diff
changeset
|
469 |
(*Count new hyps so that they can be rotated*) |
cc3e8453d7f0
More deterministic and therefore faster (sometimes) proof reconstruction
paulson
parents:
4354
diff
changeset
|
470 |
fun nNewHyps [] = 0 |
18177 | 471 |
| nNewHyps (Const ("*Goal*", _) $ _ :: Ps) = nNewHyps Ps |
4391
cc3e8453d7f0
More deterministic and therefore faster (sometimes) proof reconstruction
paulson
parents:
4354
diff
changeset
|
472 |
| nNewHyps (P::Ps) = 1 + nNewHyps Ps; |
2854 | 473 |
|
5463
a5479f5cd482
Allows more backtracking in proof reconstruction, making it slower but more
paulson
parents:
5411
diff
changeset
|
474 |
fun rot_tac [] i st = Seq.single st |
4391
cc3e8453d7f0
More deterministic and therefore faster (sometimes) proof reconstruction
paulson
parents:
4354
diff
changeset
|
475 |
| rot_tac (0::ks) i st = rot_tac ks (i+1) st |
31945 | 476 |
| rot_tac (k::ks) i st = rot_tac ks (i+1) (Thm.rotate_rule (~k) i st); |
4391
cc3e8453d7f0
More deterministic and therefore faster (sometimes) proof reconstruction
paulson
parents:
4354
diff
changeset
|
477 |
in |
cc3e8453d7f0
More deterministic and therefore faster (sometimes) proof reconstruction
paulson
parents:
4354
diff
changeset
|
478 |
fun rot_subgoals_tac (rot, rl) = |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
479 |
rot_tac (if rot then map nNewHyps rl else []) |
4391
cc3e8453d7f0
More deterministic and therefore faster (sometimes) proof reconstruction
paulson
parents:
4354
diff
changeset
|
480 |
end; |
cc3e8453d7f0
More deterministic and therefore faster (sometimes) proof reconstruction
paulson
parents:
4354
diff
changeset
|
481 |
|
2854 | 482 |
|
54942
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
483 |
fun cond_tracing true msg = tracing (msg ()) |
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
484 |
| cond_tracing false _ = (); |
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
485 |
|
42804 | 486 |
fun TRACE ctxt rl tac i st = |
61268 | 487 |
(cond_tracing (Config.get ctxt trace) (fn () => Thm.string_of_thm ctxt rl); tac i st); |
2854 | 488 |
|
5343
871b77df79a0
new version, more resistant to PROOF FAILED. Now it distinguishes between
paulson
parents:
4653
diff
changeset
|
489 |
(*Resolution/matching tactics: if upd then the proof state may be updated. |
871b77df79a0
new version, more resistant to PROOF FAILED. Now it distinguishes between
paulson
parents:
4653
diff
changeset
|
490 |
Matching makes the tactics more deterministic in the presence of Vars.*) |
59498
50b60f501b05
proper context for resolve_tac, eresolve_tac, dresolve_tac, forward_tac etc.;
wenzelm
parents:
58963
diff
changeset
|
491 |
fun emtac ctxt upd rl = |
50b60f501b05
proper context for resolve_tac, eresolve_tac, dresolve_tac, forward_tac etc.;
wenzelm
parents:
58963
diff
changeset
|
492 |
TRACE ctxt rl (if upd then eresolve_tac ctxt [rl] else ematch_tac ctxt [rl]); |
50b60f501b05
proper context for resolve_tac, eresolve_tac, dresolve_tac, forward_tac etc.;
wenzelm
parents:
58963
diff
changeset
|
493 |
|
50b60f501b05
proper context for resolve_tac, eresolve_tac, dresolve_tac, forward_tac etc.;
wenzelm
parents:
58963
diff
changeset
|
494 |
fun rmtac ctxt upd rl = |
50b60f501b05
proper context for resolve_tac, eresolve_tac, dresolve_tac, forward_tac etc.;
wenzelm
parents:
58963
diff
changeset
|
495 |
TRACE ctxt rl (if upd then resolve_tac ctxt [rl] else match_tac ctxt [rl]); |
5343
871b77df79a0
new version, more resistant to PROOF FAILED. Now it distinguishes between
paulson
parents:
4653
diff
changeset
|
496 |
|
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
497 |
(*Tableau rule from elimination rule. |
5343
871b77df79a0
new version, more resistant to PROOF FAILED. Now it distinguishes between
paulson
parents:
4653
diff
changeset
|
498 |
Flag "upd" says that the inference updated the branch. |
871b77df79a0
new version, more resistant to PROOF FAILED. Now it distinguishes between
paulson
parents:
4653
diff
changeset
|
499 |
Flag "dup" requests duplication of the affected formula.*) |
61056 | 500 |
fun fromRule (state as State {ctxt, ...}) vars rl0 = |
501 |
let |
|
502 |
val thy = Proof_Context.theory_of ctxt |
|
503 |
val rl = Thm.transfer thy rl0 |
|
504 |
val trl = rl |> Thm.prop_of |> fromTerm thy |> convertRule state vars |
|
505 |
fun tac (upd, dup,rot) i = |
|
506 |
emtac ctxt upd (if dup then rev_dup_elim ctxt rl else rl) i THEN |
|
507 |
rot_subgoals_tac (rot, #2 trl) i |
|
508 |
in SOME (trl, tac) end |
|
32091
30e2ffbba718
proper context for Display.pretty_thm etc. or old-style versions Display.pretty_thm_global, Display.pretty_thm_without_context etc.;
wenzelm
parents:
31945
diff
changeset
|
509 |
handle |
30e2ffbba718
proper context for Display.pretty_thm etc. or old-style versions Display.pretty_thm_global, Display.pretty_thm_without_context etc.;
wenzelm
parents:
31945
diff
changeset
|
510 |
ElimBadPrem => (*reject: prems don't preserve conclusion*) |
54942
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
511 |
(if Context_Position.is_visible ctxt then |
61268 | 512 |
warning ("Ignoring weak elimination rule\n" ^ Thm.string_of_thm ctxt rl0) |
54942
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
513 |
else (); |
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
514 |
Option.NONE) |
32091
30e2ffbba718
proper context for Display.pretty_thm etc. or old-style versions Display.pretty_thm_global, Display.pretty_thm_without_context etc.;
wenzelm
parents:
31945
diff
changeset
|
515 |
| ElimBadConcl => (*ignore: conclusion is not just a variable*) |
54942
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
516 |
(cond_tracing (Config.get ctxt trace) |
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
517 |
(fn () => "Ignoring ill-formed elimination rule:\n" ^ |
61268 | 518 |
"conclusion should be a variable\n" ^ Thm.string_of_thm ctxt rl0); |
32091
30e2ffbba718
proper context for Display.pretty_thm etc. or old-style versions Display.pretty_thm_global, Display.pretty_thm_without_context etc.;
wenzelm
parents:
31945
diff
changeset
|
519 |
Option.NONE); |
2854 | 520 |
|
521 |
||
3101
e8a92f497295
Again "norm" DOES NOT normalize bodies of abstractions
paulson
parents:
3092
diff
changeset
|
522 |
(*** Conversion of Introduction Rules ***) |
2854 | 523 |
|
524 |
fun convertIntrPrem t = mkGoal (strip_imp_concl t) :: strip_imp_prems t; |
|
525 |
||
43349 | 526 |
fun convertIntrRule state vars t = |
2854 | 527 |
let val Ps = strip_imp_prems t |
528 |
val P = strip_imp_concl t |
|
43349 | 529 |
in (mkGoal P, map (convertIntrPrem o skoPrem state vars) Ps) |
2854 | 530 |
end; |
531 |
||
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
532 |
(*Tableau rule from introduction rule. |
5343
871b77df79a0
new version, more resistant to PROOF FAILED. Now it distinguishes between
paulson
parents:
4653
diff
changeset
|
533 |
Flag "upd" says that the inference updated the branch. |
871b77df79a0
new version, more resistant to PROOF FAILED. Now it distinguishes between
paulson
parents:
4653
diff
changeset
|
534 |
Flag "dup" requests duplication of the affected formula. |
60943 | 535 |
Since unsafe rules are now delayed, "dup" is always FALSE for |
5343
871b77df79a0
new version, more resistant to PROOF FAILED. Now it distinguishes between
paulson
parents:
4653
diff
changeset
|
536 |
introduction rules.*) |
61056 | 537 |
fun fromIntrRule (state as State {ctxt, ...}) vars rl0 = |
538 |
let |
|
539 |
val thy = Proof_Context.theory_of ctxt |
|
540 |
val rl = Thm.transfer thy rl0 |
|
541 |
val trl = rl |> Thm.prop_of |> fromTerm thy |> convertIntrRule state vars |
|
542 |
fun tac (upd,dup,rot) i = |
|
543 |
rmtac ctxt upd (if dup then Classical.dup_intr rl else rl) i THEN |
|
544 |
rot_subgoals_tac (rot, #2 trl) i |
|
2854 | 545 |
in (trl, tac) end; |
546 |
||
547 |
||
3030 | 548 |
val dummyVar = Term.Var (("etc",0), dummyT); |
2854 | 549 |
|
550 |
(*Convert from prototerms to ordinary terms with dummy types |
|
2924
af506c35b4ed
Control over excessive branching by applying a log2 penalty
paulson
parents:
2894
diff
changeset
|
551 |
Ignore abstractions; identify all Vars; STOP at given depth*) |
af506c35b4ed
Control over excessive branching by applying a log2 penalty
paulson
parents:
2894
diff
changeset
|
552 |
fun toTerm 0 _ = dummyVar |
18177 | 553 |
| toTerm d (Const(a,_)) = Term.Const (a,dummyT) (*no need to convert typargs*) |
2924
af506c35b4ed
Control over excessive branching by applying a log2 penalty
paulson
parents:
2894
diff
changeset
|
554 |
| toTerm d (Skolem(a,_)) = Term.Const (a,dummyT) |
af506c35b4ed
Control over excessive branching by applying a log2 penalty
paulson
parents:
2894
diff
changeset
|
555 |
| toTerm d (Free a) = Term.Free (a,dummyT) |
af506c35b4ed
Control over excessive branching by applying a log2 penalty
paulson
parents:
2894
diff
changeset
|
556 |
| toTerm d (Bound i) = Term.Bound i |
af506c35b4ed
Control over excessive branching by applying a log2 penalty
paulson
parents:
2894
diff
changeset
|
557 |
| toTerm d (Var _) = dummyVar |
af506c35b4ed
Control over excessive branching by applying a log2 penalty
paulson
parents:
2894
diff
changeset
|
558 |
| toTerm d (Abs(a,_)) = dummyVar |
af506c35b4ed
Control over excessive branching by applying a log2 penalty
paulson
parents:
2894
diff
changeset
|
559 |
| toTerm d (f $ u) = Term.$ (toTerm d f, toTerm (d-1) u); |
2854 | 560 |
|
561 |
||
43349 | 562 |
fun netMkRules state P vars (nps: Classical.netpair list) = |
2854 | 563 |
case P of |
18177 | 564 |
(Const ("*Goal*", _) $ G) => |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
565 |
let val pG = mk_Trueprop (toTerm 2 G) |
19482
9f11af8f7ef9
tuned basic list operators (flat, maps, map_filter);
wenzelm
parents:
19037
diff
changeset
|
566 |
val intrs = maps (fn (inet,_) => Net.unify_term inet pG) nps |
43349 | 567 |
in map (fromIntrRule state vars o #2) (order_list intrs) end |
2854 | 568 |
| _ => |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
569 |
let val pP = mk_Trueprop (toTerm 3 P) |
19482
9f11af8f7ef9
tuned basic list operators (flat, maps, map_filter);
wenzelm
parents:
19037
diff
changeset
|
570 |
val elims = maps (fn (_,enet) => Net.unify_term enet pP) nps |
43349 | 571 |
in map_filter (fromRule state vars o #2) (order_list elims) end; |
3092 | 572 |
|
573 |
||
574 |
(*Normalize a branch--for tracing*) |
|
575 |
fun norm2 (G,md) = (norm G, md); |
|
576 |
||
577 |
fun normLev (Gs,Hs) = (map norm2 Gs, map norm2 Hs); |
|
578 |
||
5463
a5479f5cd482
Allows more backtracking in proof reconstruction, making it slower but more
paulson
parents:
5411
diff
changeset
|
579 |
fun normBr {pairs, lits, vars, lim} = |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
580 |
{pairs = map normLev pairs, |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
581 |
lits = map norm lits, |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
582 |
vars = vars, |
5463
a5479f5cd482
Allows more backtracking in proof reconstruction, making it slower but more
paulson
parents:
5411
diff
changeset
|
583 |
lim = lim}; |
3092 | 584 |
|
585 |
||
4065 | 586 |
val dummyTVar = Term.TVar(("a",0), []); |
3092 | 587 |
val dummyVar2 = Term.Var(("var",0), dummyT); |
588 |
||
26938 | 589 |
(*convert blast_tac's type representation to real types for tracing*) |
4065 | 590 |
fun showType (Free a) = Term.TFree (a,[]) |
591 |
| showType (Var _) = dummyTVar |
|
592 |
| showType t = |
|
593 |
(case strip_comb t of |
|
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
594 |
(Const (a, _), us) => Term.Type(a, map showType us) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
595 |
| _ => dummyT); |
4065 | 596 |
|
597 |
(*Display top-level overloading if any*) |
|
18177 | 598 |
fun topType thy (Const (c, ts)) = SOME (Sign.const_instance thy (c, map showType ts)) |
599 |
| topType thy (Abs(a,t)) = topType thy t |
|
600 |
| topType thy (f $ u) = (case topType thy f of NONE => topType thy u | some => some) |
|
601 |
| topType _ _ = NONE; |
|
4065 | 602 |
|
603 |
||
3092 | 604 |
(*Convert from prototerms to ordinary terms with dummy types for tracing*) |
18177 | 605 |
fun showTerm d (Const (a,_)) = Term.Const (a,dummyT) |
3092 | 606 |
| showTerm d (Skolem(a,_)) = Term.Const (a,dummyT) |
32740 | 607 |
| showTerm d (Free a) = Term.Free (a,dummyT) |
608 |
| showTerm d (Bound i) = Term.Bound i |
|
609 |
| showTerm d (Var (Unsynchronized.ref(SOME u))) = showTerm d u |
|
610 |
| showTerm d (Var (Unsynchronized.ref NONE)) = dummyVar2 |
|
3092 | 611 |
| showTerm d (Abs(a,t)) = if d=0 then dummyVar |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
612 |
else Term.Abs(a, dummyT, showTerm (d-1) t) |
3092 | 613 |
| showTerm d (f $ u) = if d=0 then dummyVar |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
614 |
else Term.$ (showTerm d f, showTerm (d-1) u); |
3092 | 615 |
|
42801
da4ad5f98953
proper Proof.context -- eliminated global operations;
wenzelm
parents:
42793
diff
changeset
|
616 |
fun string_of ctxt d t = Syntax.string_of_term ctxt (showTerm d t); |
3092 | 617 |
|
19037 | 618 |
(*Convert a Goal to an ordinary Not. Used also in dup_intr, where a goal like |
619 |
Ex(P) is duplicated as the assumption ~Ex(P). *) |
|
620 |
fun negOfGoal (Const ("*Goal*", _) $ G) = negate G |
|
621 |
| negOfGoal G = G; |
|
622 |
||
623 |
fun negOfGoal2 (G,md) = (negOfGoal G, md); |
|
624 |
||
625 |
(*Converts all Goals to Nots in the safe parts of a branch. They could |
|
626 |
have been moved there from the literals list after substitution (equalSubst). |
|
627 |
There can be at most one--this function could be made more efficient.*) |
|
60943 | 628 |
fun negOfGoals pairs = map (fn (Gs, unsafe) => (map negOfGoal2 Gs, unsafe)) pairs; |
19037 | 629 |
|
630 |
(*Tactic. Convert *Goal* to negated assumption in FIRST position*) |
|
42804 | 631 |
fun negOfGoal_tac ctxt i = |
59498
50b60f501b05
proper context for resolve_tac, eresolve_tac, dresolve_tac, forward_tac etc.;
wenzelm
parents:
58963
diff
changeset
|
632 |
TRACE ctxt Data.ccontr (resolve_tac ctxt [Data.ccontr]) i THEN rotate_tac ~1 i; |
19037 | 633 |
|
42801
da4ad5f98953
proper Proof.context -- eliminated global operations;
wenzelm
parents:
42793
diff
changeset
|
634 |
fun traceTerm ctxt t = |
da4ad5f98953
proper Proof.context -- eliminated global operations;
wenzelm
parents:
42793
diff
changeset
|
635 |
let val thy = Proof_Context.theory_of ctxt |
da4ad5f98953
proper Proof.context -- eliminated global operations;
wenzelm
parents:
42793
diff
changeset
|
636 |
val t' = norm (negOfGoal t) |
da4ad5f98953
proper Proof.context -- eliminated global operations;
wenzelm
parents:
42793
diff
changeset
|
637 |
val stm = string_of ctxt 8 t' |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
638 |
in |
24062
845c0d693328
explicit global state argument -- no longer CRITICAL;
wenzelm
parents:
23985
diff
changeset
|
639 |
case topType thy t' of |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
640 |
NONE => stm (*no type to attach*) |
54943
1276861f2724
avoid hard tabs in output -- somewhat ill-defined;
wenzelm
parents:
54942
diff
changeset
|
641 |
| SOME T => stm ^ " :: " ^ Syntax.string_of_typ ctxt T |
4065 | 642 |
end; |
3092 | 643 |
|
644 |
||
645 |
(*Print tracing information at each iteration of prover*) |
|
54942
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
646 |
fun trace_prover (State {ctxt, fullTrace, ...}) brs = |
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
647 |
let fun printPairs (((G,_)::_,_)::_) = tracing (traceTerm ctxt G) |
54943
1276861f2724
avoid hard tabs in output -- somewhat ill-defined;
wenzelm
parents:
54942
diff
changeset
|
648 |
| printPairs (([],(H,_)::_)::_) = tracing (traceTerm ctxt H ^ " (Unsafe)") |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
649 |
| printPairs _ = () |
5463
a5479f5cd482
Allows more backtracking in proof reconstruction, making it slower but more
paulson
parents:
5411
diff
changeset
|
650 |
fun printBrs (brs0 as {pairs, lits, lim, ...} :: brs) = |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
651 |
(fullTrace := brs0 :: !fullTrace; |
54942
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
652 |
List.app (fn _ => tracing "+") brs; |
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
653 |
tracing (" [" ^ string_of_int lim ^ "] "); |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
654 |
printPairs pairs; |
54942
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
655 |
tracing "") |
42804 | 656 |
in if Config.get ctxt trace then printBrs (map normBr brs) else () end; |
3092 | 657 |
|
658 |
(*Tracing: variables updated in the last branch operation?*) |
|
42801
da4ad5f98953
proper Proof.context -- eliminated global operations;
wenzelm
parents:
42793
diff
changeset
|
659 |
fun traceVars (State {ctxt, ntrail, trail, ...}) ntrl = |
42804 | 660 |
if Config.get ctxt trace then |
4065 | 661 |
(case !ntrail-ntrl of |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
662 |
0 => () |
54943
1276861f2724
avoid hard tabs in output -- somewhat ill-defined;
wenzelm
parents:
54942
diff
changeset
|
663 |
| 1 => tracing " 1 variable UPDATED:" |
1276861f2724
avoid hard tabs in output -- somewhat ill-defined;
wenzelm
parents:
54942
diff
changeset
|
664 |
| n => tracing (" " ^ string_of_int n ^ " variables UPDATED:"); |
4065 | 665 |
(*display the instantiations themselves, though no variable names*) |
54942
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
666 |
List.app (fn v => tracing (" " ^ string_of ctxt 4 (the (!v)))) |
4065 | 667 |
(List.take(!trail, !ntrail-ntrl)); |
54942
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
668 |
tracing "") |
3092 | 669 |
else (); |
670 |
||
671 |
(*Tracing: how many new branches are created?*) |
|
42804 | 672 |
fun traceNew true prems = |
673 |
(case length prems of |
|
54942
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
674 |
0 => tracing "branch closed by rule" |
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
675 |
| 1 => tracing "branch extended (1 new subgoal)" |
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
676 |
| n => tracing ("branch split: "^ string_of_int n ^ " new subgoals")) |
42804 | 677 |
| traceNew _ _ = (); |
3092 | 678 |
|
679 |
||
680 |
||
2854 | 681 |
(*** Code for handling equality: naive substitution, like hyp_subst_tac ***) |
682 |
||
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
683 |
(*Replace the ATOMIC term "old" by "new" in t*) |
2854 | 684 |
fun subst_atomic (old,new) t = |
32740 | 685 |
let fun subst (Var(Unsynchronized.ref(SOME u))) = subst u |
686 |
| subst (Abs(a,body)) = Abs(a, subst body) |
|
687 |
| subst (f$t) = subst f $ subst t |
|
688 |
| subst t = if t aconv old then new else t |
|
2854 | 689 |
in subst t end; |
690 |
||
691 |
(*Eta-contract a term from outside: just enough to reduce it to an atom*) |
|
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
692 |
fun eta_contract_atom (t0 as Abs(a, body)) = |
2854 | 693 |
(case eta_contract2 body of |
20664 | 694 |
f $ Bound 0 => if member (op =) (loose_bnos f) 0 then t0 |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
695 |
else eta_contract_atom (incr_boundvars ~1 f) |
2854 | 696 |
| _ => t0) |
697 |
| eta_contract_atom t = t |
|
698 |
and eta_contract2 (f$t) = f $ eta_contract_atom t |
|
699 |
| eta_contract2 t = eta_contract_atom t; |
|
700 |
||
701 |
||
702 |
(*When can we safely delete the equality? |
|
703 |
Not if it equates two constants; consider 0=1. |
|
704 |
Not if it resembles x=t[x], since substitution does not eliminate x. |
|
705 |
Not if it resembles ?x=0; another goal could instantiate ?x to Suc(i) |
|
706 |
Prefer to eliminate Bound variables if possible. |
|
707 |
Result: true = use as is, false = reorient first *) |
|
708 |
||
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
709 |
(*Can t occur in u? For substitution. |
4354
7f4da01bdf0e
Fixed the treatment of substitution for equations, restricting occurrences of
paulson
parents:
4323
diff
changeset
|
710 |
Does NOT examine the args of Skolem terms: substitution does not affect them. |
4196
9953c0995b79
Now applies "map negOfGoal" to lits when expanding haz rules.
paulson
parents:
4149
diff
changeset
|
711 |
REFLEXIVE because hyp_subst_tac fails on x=x.*) |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
712 |
fun substOccur t = |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
713 |
let (*NO vars are permitted in u except the arguments of t, if it is |
4354
7f4da01bdf0e
Fixed the treatment of substitution for equations, restricting occurrences of
paulson
parents:
4323
diff
changeset
|
714 |
a Skolem term. This ensures that no equations are deleted that could |
7f4da01bdf0e
Fixed the treatment of substitution for equations, restricting occurrences of
paulson
parents:
4323
diff
changeset
|
715 |
be instantiated to a cycle. For example, x=?a is rejected because ?a |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
716 |
could be instantiated to Suc(x).*) |
4354
7f4da01bdf0e
Fixed the treatment of substitution for equations, restricting occurrences of
paulson
parents:
4323
diff
changeset
|
717 |
val vars = case t of |
7f4da01bdf0e
Fixed the treatment of substitution for equations, restricting occurrences of
paulson
parents:
4323
diff
changeset
|
718 |
Skolem(_,vars) => vars |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
719 |
| _ => [] |
4354
7f4da01bdf0e
Fixed the treatment of substitution for equations, restricting occurrences of
paulson
parents:
4323
diff
changeset
|
720 |
fun occEq u = (t aconv u) orelse occ u |
32740 | 721 |
and occ (Var(Unsynchronized.ref(SOME u))) = occEq u |
722 |
| occ (Var v) = not (mem_var (v, vars)) |
|
723 |
| occ (Abs(_,u)) = occEq u |
|
724 |
| occ (f$u) = occEq u orelse occEq f |
|
725 |
| occ _ = false; |
|
2854 | 726 |
in occEq end; |
727 |
||
3092 | 728 |
exception DEST_EQ; |
729 |
||
18177 | 730 |
(*Take apart an equality. NO constant Trueprop*) |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
731 |
fun dest_eq (Const (c, _) $ t $ u) = |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
732 |
if c = Data.equality_name then (eta_contract_atom t, eta_contract_atom u) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
733 |
else raise DEST_EQ |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
734 |
| dest_eq _ = raise DEST_EQ; |
3092 | 735 |
|
4196
9953c0995b79
Now applies "map negOfGoal" to lits when expanding haz rules.
paulson
parents:
4149
diff
changeset
|
736 |
(*Reject the equality if u occurs in (or equals!) t*) |
2854 | 737 |
fun check (t,u,v) = if substOccur t u then raise DEST_EQ else v; |
738 |
||
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
739 |
(*IF the goal is an equality with a substitutable variable |
2854 | 740 |
THEN orient that equality ELSE raise exception DEST_EQ*) |
3092 | 741 |
fun orientGoal (t,u) = case (t,u) of |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
742 |
(Skolem _, _) => check(t,u,(t,u)) (*eliminates t*) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
743 |
| (_, Skolem _) => check(u,t,(u,t)) (*eliminates u*) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
744 |
| (Free _, _) => check(t,u,(t,u)) (*eliminates t*) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
745 |
| (_, Free _) => check(u,t,(u,t)) (*eliminates u*) |
2854 | 746 |
| _ => raise DEST_EQ; |
747 |
||
2894 | 748 |
(*Substitute through the branch if an equality goal (else raise DEST_EQ). |
749 |
Moves affected literals back into the branch, but it is not clear where |
|
4391
cc3e8453d7f0
More deterministic and therefore faster (sometimes) proof reconstruction
paulson
parents:
4354
diff
changeset
|
750 |
they should go: this could make proofs fail.*) |
42801
da4ad5f98953
proper Proof.context -- eliminated global operations;
wenzelm
parents:
42793
diff
changeset
|
751 |
fun equalSubst ctxt (G, {pairs, lits, vars, lim}) = |
3092 | 752 |
let val (t,u) = orientGoal(dest_eq G) |
753 |
val subst = subst_atomic (t,u) |
|
2854 | 754 |
fun subst2(G,md) = (subst G, md) |
4466
305390f23734
Better equality handling in Blast_tac, usingd a new variant of hyp_subst_tac
paulson
parents:
4391
diff
changeset
|
755 |
(*substitute throughout list; extract affected formulae*) |
305390f23734
Better equality handling in Blast_tac, usingd a new variant of hyp_subst_tac
paulson
parents:
4391
diff
changeset
|
756 |
fun subForm ((G,md), (changed, pairs)) = |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
757 |
let val nG = subst G |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
758 |
in if nG aconv G then (changed, (G,md)::pairs) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
759 |
else ((nG,md)::changed, pairs) |
2924
af506c35b4ed
Control over excessive branching by applying a log2 penalty
paulson
parents:
2894
diff
changeset
|
760 |
end |
4466
305390f23734
Better equality handling in Blast_tac, usingd a new variant of hyp_subst_tac
paulson
parents:
4391
diff
changeset
|
761 |
(*substitute throughout "stack frame"; extract affected formulae*) |
305390f23734
Better equality handling in Blast_tac, usingd a new variant of hyp_subst_tac
paulson
parents:
4391
diff
changeset
|
762 |
fun subFrame ((Gs,Hs), (changed, frames)) = |
30190 | 763 |
let val (changed', Gs') = List.foldr subForm (changed, []) Gs |
764 |
val (changed'', Hs') = List.foldr subForm (changed', []) Hs |
|
4466
305390f23734
Better equality handling in Blast_tac, usingd a new variant of hyp_subst_tac
paulson
parents:
4391
diff
changeset
|
765 |
in (changed'', (Gs',Hs')::frames) end |
305390f23734
Better equality handling in Blast_tac, usingd a new variant of hyp_subst_tac
paulson
parents:
4391
diff
changeset
|
766 |
(*substitute throughout literals; extract affected ones*) |
305390f23734
Better equality handling in Blast_tac, usingd a new variant of hyp_subst_tac
paulson
parents:
4391
diff
changeset
|
767 |
fun subLit (lit, (changed, nlits)) = |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
768 |
let val nlit = subst lit |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
769 |
in if nlit aconv lit then (changed, nlit::nlits) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
770 |
else ((nlit,true)::changed, nlits) |
2854 | 771 |
end |
30190 | 772 |
val (changed, lits') = List.foldr subLit ([], []) lits |
773 |
val (changed', pairs') = List.foldr subFrame (changed, []) pairs |
|
54942
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
774 |
in if Config.get ctxt trace then tracing ("Substituting " ^ traceTerm ctxt u ^ |
42801
da4ad5f98953
proper Proof.context -- eliminated global operations;
wenzelm
parents:
42793
diff
changeset
|
775 |
" for " ^ traceTerm ctxt t ^ " in branch" ) |
3092 | 776 |
else (); |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
777 |
{pairs = (changed',[])::pairs', (*affected formulas, and others*) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
778 |
lits = lits', (*unaffected literals*) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
779 |
vars = vars, |
5463
a5479f5cd482
Allows more backtracking in proof reconstruction, making it slower but more
paulson
parents:
5411
diff
changeset
|
780 |
lim = lim} |
2854 | 781 |
end; |
782 |
||
783 |
||
784 |
exception NEWBRANCHES and CLOSEF; |
|
785 |
||
786 |
exception PROVE; |
|
787 |
||
4391
cc3e8453d7f0
More deterministic and therefore faster (sometimes) proof reconstruction
paulson
parents:
4354
diff
changeset
|
788 |
(*Trying eq_contr_tac first INCREASES the effort, slowing reconstruction*) |
58957 | 789 |
fun contr_tac ctxt = |
58963
26bf09b95dda
proper context for assume_tac (atac remains as fall-back without context);
wenzelm
parents:
58958
diff
changeset
|
790 |
ematch_tac ctxt [Data.notE] THEN' (eq_assume_tac ORELSE' assume_tac ctxt); |
2854 | 791 |
|
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
792 |
(*Try to unify complementary literals and return the corresponding tactic. *) |
24062
845c0d693328
explicit global state argument -- no longer CRITICAL;
wenzelm
parents:
23985
diff
changeset
|
793 |
fun tryClose state (G, L) = |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
794 |
let |
42804 | 795 |
val State {ctxt, ...} = state; |
796 |
val eContr_tac = TRACE ctxt Data.notE contr_tac; |
|
58963
26bf09b95dda
proper context for assume_tac (atac remains as fall-back without context);
wenzelm
parents:
58958
diff
changeset
|
797 |
val eAssume_tac = TRACE ctxt asm_rl (eq_assume_tac ORELSE' assume_tac ctxt); |
24062
845c0d693328
explicit global state argument -- no longer CRITICAL;
wenzelm
parents:
23985
diff
changeset
|
798 |
fun close t u tac = if unify state ([], t, u) then SOME tac else NONE; |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
799 |
fun arg (_ $ t) = t; |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
800 |
in |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
801 |
if isGoal G then close (arg G) L eAssume_tac |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
802 |
else if isGoal L then close G (arg L) eAssume_tac |
58957 | 803 |
else if isNot G then close (arg G) L (eContr_tac ctxt) |
804 |
else if isNot L then close G (arg L) (eContr_tac ctxt) |
|
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
805 |
else NONE |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
806 |
end; |
2854 | 807 |
|
808 |
(*Were there Skolem terms in the premise? Must NOT chase Vars*) |
|
809 |
fun hasSkolem (Skolem _) = true |
|
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
810 |
| hasSkolem (Abs (_,body)) = hasSkolem body |
42801
da4ad5f98953
proper Proof.context -- eliminated global operations;
wenzelm
parents:
42793
diff
changeset
|
811 |
| hasSkolem (f$t) = hasSkolem f orelse hasSkolem t |
2854 | 812 |
| hasSkolem _ = false; |
813 |
||
814 |
(*Attach the right "may duplicate" flag to new formulae: if they contain |
|
815 |
Skolem terms then allow duplication.*) |
|
816 |
fun joinMd md [] = [] |
|
817 |
| joinMd md (G::Gs) = (G, hasSkolem G orelse md) :: joinMd md Gs; |
|
818 |
||
819 |
||
820 |
(** Backtracking and Pruning **) |
|
821 |
||
822 |
(*clashVar vars (n,trail) determines whether any of the last n elements |
|
823 |
of "trail" occur in "vars" OR in their instantiations*) |
|
824 |
fun clashVar [] = (fn _ => false) |
|
825 |
| clashVar vars = |
|
826 |
let fun clash (0, _) = false |
|
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
827 |
| clash (_, []) = false |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
828 |
| clash (n, v::vs) = exists (varOccur v) vars orelse clash(n-1,vs) |
2854 | 829 |
in clash end; |
830 |
||
831 |
||
832 |
(*nbrs = # of branches just prior to closing this one. Delete choice points |
|
833 |
for goals proved by the latest inference, provided NO variables in the |
|
834 |
next branch have been updated.*) |
|
24062
845c0d693328
explicit global state argument -- no longer CRITICAL;
wenzelm
parents:
23985
diff
changeset
|
835 |
fun prune _ (1, nxtVars, choices) = choices (*DON'T prune at very end: allow |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
836 |
backtracking over bad proofs*) |
42804 | 837 |
| prune (State {ctxt, ntrail, trail, ...}) (nbrs: int, nxtVars, choices) = |
2854 | 838 |
let fun traceIt last = |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
839 |
let val ll = length last |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
840 |
and lc = length choices |
42804 | 841 |
in if Config.get ctxt trace andalso ll<lc then |
54942
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
842 |
(tracing ("Pruning " ^ string_of_int(lc-ll) ^ " levels"); |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
843 |
last) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
844 |
else last |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
845 |
end |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
846 |
fun pruneAux (last, _, _, []) = last |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
847 |
| pruneAux (last, ntrl, trl, (ntrl',nbrs',exn) :: choices) = |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
848 |
if nbrs' < nbrs |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
849 |
then last (*don't backtrack beyond first solution of goal*) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
850 |
else if nbrs' > nbrs then pruneAux (last, ntrl, trl, choices) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
851 |
else (* nbrs'=nbrs *) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
852 |
if clashVar nxtVars (ntrl-ntrl', trl) then last |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
853 |
else (*no clashes: can go back at least this far!*) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
854 |
pruneAux(choices, ntrl', List.drop(trl, ntrl-ntrl'), |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
855 |
choices) |
2854 | 856 |
in traceIt (pruneAux (choices, !ntrail, !trail, choices)) end; |
857 |
||
5463
a5479f5cd482
Allows more backtracking in proof reconstruction, making it slower but more
paulson
parents:
5411
diff
changeset
|
858 |
fun nextVars ({pairs, lits, vars, lim} :: _) = map Var vars |
a5479f5cd482
Allows more backtracking in proof reconstruction, making it slower but more
paulson
parents:
5411
diff
changeset
|
859 |
| nextVars [] = []; |
2854 | 860 |
|
42804 | 861 |
fun backtrack trace (choices as (ntrl, nbrs, exn)::_) = |
54942
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
862 |
(cond_tracing trace |
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
863 |
(fn () => "Backtracking; now there are " ^ string_of_int nbrs ^ " branches"); |
3083 | 864 |
raise exn) |
42804 | 865 |
| backtrack _ _ = raise PROVE; |
2854 | 866 |
|
2894 | 867 |
(*Add the literal G, handling *Goal* and detecting duplicates.*) |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
868 |
fun addLit (Const ("*Goal*", _) $ G, lits) = |
2894 | 869 |
(*New literal is a *Goal*, so change all other Goals to Nots*) |
18177 | 870 |
let fun bad (Const ("*Goal*", _) $ _) = true |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
871 |
| bad (Const (c, _) $ G') = c = Data.not_name andalso G aconv G' |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
872 |
| bad _ = false; |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
873 |
fun change [] = [] |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
874 |
| change (lit :: lits) = |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
875 |
(case lit of |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
876 |
Const (c, _) $ G' => |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
877 |
if c = "*Goal*" orelse c = Data.not_name then |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
878 |
if G aconv G' then change lits |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
879 |
else negate G' :: change lits |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
880 |
else lit :: change lits |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
881 |
| _ => lit :: change lits) |
2854 | 882 |
in |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
883 |
Const ("*Goal*", []) $ G :: (if exists bad lits then change lits else lits) |
2854 | 884 |
end |
885 |
| addLit (G,lits) = ins_term(G, lits) |
|
886 |
||
887 |
||
2952 | 888 |
(*For calculating the "penalty" to assess on a branching factor of n |
889 |
log2 seems a little too severe*) |
|
3083 | 890 |
fun log n = if n<4 then 0 else 1 + log(n div 4); |
2924
af506c35b4ed
Control over excessive branching by applying a log2 penalty
paulson
parents:
2894
diff
changeset
|
891 |
|
af506c35b4ed
Control over excessive branching by applying a log2 penalty
paulson
parents:
2894
diff
changeset
|
892 |
|
3021
39806db47be9
Loop detection: before expanding a haz formula, see whether it is a duplicate
paulson
parents:
2999
diff
changeset
|
893 |
(*match(t,u) says whether the term u might be an instance of the pattern t |
39806db47be9
Loop detection: before expanding a haz formula, see whether it is a duplicate
paulson
parents:
2999
diff
changeset
|
894 |
Used to detect "recursive" rules such as transitivity*) |
39806db47be9
Loop detection: before expanding a haz formula, see whether it is a duplicate
paulson
parents:
2999
diff
changeset
|
895 |
fun match (Var _) u = true |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
896 |
| match (Const (a,tas)) (Const (b,tbs)) = |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
897 |
a = "*Goal*" andalso b = Data.not_name orelse |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
898 |
a = Data.not_name andalso b = "*Goal*" orelse |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
899 |
a = b andalso matchs tas tbs |
4065 | 900 |
| match (Free a) (Free b) = (a=b) |
901 |
| match (Bound i) (Bound j) = (i=j) |
|
902 |
| match (Abs(_,t)) (Abs(_,u)) = match t u |
|
903 |
| match (f$t) (g$u) = match f g andalso match t u |
|
18177 | 904 |
| match t u = false |
905 |
and matchs [] [] = true |
|
906 |
| matchs (t :: ts) (u :: us) = match t u andalso matchs ts us; |
|
3021
39806db47be9
Loop detection: before expanding a haz formula, see whether it is a duplicate
paulson
parents:
2999
diff
changeset
|
907 |
|
39806db47be9
Loop detection: before expanding a haz formula, see whether it is a duplicate
paulson
parents:
2999
diff
changeset
|
908 |
|
24062
845c0d693328
explicit global state argument -- no longer CRITICAL;
wenzelm
parents:
23985
diff
changeset
|
909 |
fun printStats (State {ntried, nclosed, ...}) (b, start, tacs) = |
4323
561242f8606b
Printing of statistics including time for search & reconstruction
paulson
parents:
4300
diff
changeset
|
910 |
if b then |
54942
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
911 |
tracing (Timing.message (Timing.result start) ^ " for search. Closed: " |
41491 | 912 |
^ string_of_int (!nclosed) ^ |
913 |
" tried: " ^ string_of_int (!ntried) ^ |
|
914 |
" tactics: " ^ string_of_int (length tacs)) |
|
4323
561242f8606b
Printing of statistics including time for search & reconstruction
paulson
parents:
4300
diff
changeset
|
915 |
else (); |
561242f8606b
Printing of statistics including time for search & reconstruction
paulson
parents:
4300
diff
changeset
|
916 |
|
561242f8606b
Printing of statistics including time for search & reconstruction
paulson
parents:
4300
diff
changeset
|
917 |
|
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
918 |
(*Tableau prover based on leanTaP. Argument is a list of branches. Each |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
919 |
branch contains a list of unexpanded formulae, a list of literals, and a |
4391
cc3e8453d7f0
More deterministic and therefore faster (sometimes) proof reconstruction
paulson
parents:
4354
diff
changeset
|
920 |
bound on unsafe expansions. |
cc3e8453d7f0
More deterministic and therefore faster (sometimes) proof reconstruction
paulson
parents:
4354
diff
changeset
|
921 |
"start" is CPU time at start, for printing search time |
cc3e8453d7f0
More deterministic and therefore faster (sometimes) proof reconstruction
paulson
parents:
4354
diff
changeset
|
922 |
*) |
42801
da4ad5f98953
proper Proof.context -- eliminated global operations;
wenzelm
parents:
42793
diff
changeset
|
923 |
fun prove (state, start, brs, cont) = |
da4ad5f98953
proper Proof.context -- eliminated global operations;
wenzelm
parents:
42793
diff
changeset
|
924 |
let val State {ctxt, ntrail, nclosed, ntried, ...} = state; |
42804 | 925 |
val trace = Config.get ctxt trace; |
926 |
val stats = Config.get ctxt stats; |
|
60943 | 927 |
val {safe0_netpair, safep_netpair, unsafe_netpair, ...} = |
42793 | 928 |
Classical.rep_cs (Classical.claset_of ctxt); |
60943 | 929 |
val safeList = [safe0_netpair, safep_netpair]; |
930 |
val unsafeList = [unsafe_netpair]; |
|
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
931 |
fun prv (tacs, trs, choices, []) = |
42804 | 932 |
(printStats state (trace orelse stats, start, tacs); |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
933 |
cont (tacs, trs, choices)) (*all branches closed!*) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
934 |
| prv (tacs, trs, choices, |
60943 | 935 |
brs0 as {pairs = ((G,md)::br, unsafe)::pairs, |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
936 |
lits, vars, lim} :: brs) = |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
937 |
(*apply a safe rule only (possibly allowing instantiation); |
60943 | 938 |
defer any unsafe formulae*) |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
939 |
let exception PRV (*backtrack to precisely this recursion!*) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
940 |
val ntrl = !ntrail |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
941 |
val nbrs = length brs0 |
2854 | 942 |
val nxtVars = nextVars brs |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
943 |
val G = norm G |
43349 | 944 |
val rules = netMkRules state G vars safeList |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
945 |
(*Make a new branch, decrementing "lim" if instantiations occur*) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
946 |
fun newBr (vars',lim') prems = |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
947 |
map (fn prem => |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
948 |
if (exists isGoal prem) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
949 |
then {pairs = ((joinMd md prem, []) :: |
60943 | 950 |
negOfGoals ((br, unsafe)::pairs)), |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
951 |
lits = map negOfGoal lits, |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
952 |
vars = vars', |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
953 |
lim = lim'} |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
954 |
else {pairs = ((joinMd md prem, []) :: |
60943 | 955 |
(br, unsafe) :: pairs), |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
956 |
lits = lits, |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
957 |
vars = vars', |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
958 |
lim = lim'}) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
959 |
prems @ |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
960 |
brs |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
961 |
(*Seek a matching rule. If unifiable then add new premises |
2854 | 962 |
to branch.*) |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
963 |
fun deeper [] = raise NEWBRANCHES |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
964 |
| deeper (((P,prems),tac)::grls) = |
24062
845c0d693328
explicit global state argument -- no longer CRITICAL;
wenzelm
parents:
23985
diff
changeset
|
965 |
if unify state (add_term_vars(P,[]), P, G) |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
966 |
then (*P comes from the rule; G comes from the branch.*) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
967 |
let val updated = ntrl < !ntrail (*branch updated*) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
968 |
val lim' = if updated |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
969 |
then lim - (1+log(length rules)) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
970 |
else lim (*discourage branching updates*) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
971 |
val vars = vars_in_vars vars |
30190 | 972 |
val vars' = List.foldr add_terms_vars vars prems |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
973 |
val choices' = (ntrl, nbrs, PRV) :: choices |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
974 |
val tacs' = (tac(updated,false,true)) |
5343
871b77df79a0
new version, more resistant to PROOF FAILED. Now it distinguishes between
paulson
parents:
4653
diff
changeset
|
975 |
:: tacs (*no duplication; rotate*) |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
976 |
in |
42804 | 977 |
traceNew trace prems; traceVars state ntrl; |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
978 |
(if null prems then (*closed the branch: prune!*) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
979 |
(nclosed := !nclosed + 1; |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
980 |
prv(tacs', brs0::trs, |
24062
845c0d693328
explicit global state argument -- no longer CRITICAL;
wenzelm
parents:
23985
diff
changeset
|
981 |
prune state (nbrs, nxtVars, choices'), |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
982 |
brs)) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
983 |
else (*prems non-null*) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
984 |
if lim'<0 (*faster to kill ALL the alternatives*) |
54942
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
985 |
then (cond_tracing trace (fn () => "Excessive branching: KILLED"); |
24062
845c0d693328
explicit global state argument -- no longer CRITICAL;
wenzelm
parents:
23985
diff
changeset
|
986 |
clearTo state ntrl; raise NEWBRANCHES) |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
987 |
else |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
988 |
(ntried := !ntried + length prems - 1; |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
989 |
prv(tacs', brs0::trs, choices', |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
990 |
newBr (vars',lim') prems))) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
991 |
handle PRV => |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
992 |
if updated then |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
993 |
(*Backtrack at this level. |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
994 |
Reset Vars and try another rule*) |
24062
845c0d693328
explicit global state argument -- no longer CRITICAL;
wenzelm
parents:
23985
diff
changeset
|
995 |
(clearTo state ntrl; deeper grls) |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
996 |
else (*backtrack to previous level*) |
42804 | 997 |
backtrack trace choices |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
998 |
end |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
999 |
else deeper grls |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1000 |
(*Try to close branch by unifying with head goal*) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1001 |
fun closeF [] = raise CLOSEF |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1002 |
| closeF (L::Ls) = |
24062
845c0d693328
explicit global state argument -- no longer CRITICAL;
wenzelm
parents:
23985
diff
changeset
|
1003 |
case tryClose state (G,L) of |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1004 |
NONE => closeF Ls |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1005 |
| SOME tac => |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1006 |
let val choices' = |
54942
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
1007 |
(if trace then (tracing "branch closed"; |
24062
845c0d693328
explicit global state argument -- no longer CRITICAL;
wenzelm
parents:
23985
diff
changeset
|
1008 |
traceVars state ntrl) |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1009 |
else (); |
24062
845c0d693328
explicit global state argument -- no longer CRITICAL;
wenzelm
parents:
23985
diff
changeset
|
1010 |
prune state (nbrs, nxtVars, |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1011 |
(ntrl, nbrs, PRV) :: choices)) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1012 |
in nclosed := !nclosed + 1; |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1013 |
prv (tac::tacs, brs0::trs, choices', brs) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1014 |
handle PRV => |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1015 |
(*reset Vars and try another literal |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1016 |
[this handler is pruned if possible!]*) |
24062
845c0d693328
explicit global state argument -- no longer CRITICAL;
wenzelm
parents:
23985
diff
changeset
|
1017 |
(clearTo state ntrl; closeF Ls) |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1018 |
end |
60943 | 1019 |
(*Try to unify a queued formula (safe or unsafe) with head goal*) |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1020 |
fun closeFl [] = raise CLOSEF |
60943 | 1021 |
| closeFl ((br, unsafe)::pairs) = |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1022 |
closeF (map fst br) |
60943 | 1023 |
handle CLOSEF => closeF (map fst unsafe) |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1024 |
handle CLOSEF => closeFl pairs |
54942
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
1025 |
in |
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
1026 |
trace_prover state brs0; |
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
1027 |
if lim<0 then (cond_tracing trace (fn () => "Limit reached."); backtrack trace choices) |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1028 |
else |
58956
a816aa3ff391
proper context for compose_tac, Splitter.split_tac (relevant for unify trace options);
wenzelm
parents:
58950
diff
changeset
|
1029 |
prv (Data.hyp_subst_tac ctxt trace :: tacs, |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1030 |
brs0::trs, choices, |
42801
da4ad5f98953
proper Proof.context -- eliminated global operations;
wenzelm
parents:
42793
diff
changeset
|
1031 |
equalSubst ctxt |
60943 | 1032 |
(G, {pairs = (br,unsafe)::pairs, |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1033 |
lits = lits, vars = vars, lim = lim}) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1034 |
:: brs) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1035 |
handle DEST_EQ => closeF lits |
60943 | 1036 |
handle CLOSEF => closeFl ((br,unsafe)::pairs) |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1037 |
handle CLOSEF => deeper rules |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1038 |
handle NEWBRANCHES => |
60943 | 1039 |
(case netMkRules state G vars unsafeList of |
1040 |
[] => (*there are no plausible unsafe rules*) |
|
54942
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
1041 |
(cond_tracing trace (fn () => "moving formula to literals"); |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1042 |
prv (tacs, brs0::trs, choices, |
60943 | 1043 |
{pairs = (br,unsafe)::pairs, |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1044 |
lits = addLit(G,lits), |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1045 |
vars = vars, |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1046 |
lim = lim} :: brs)) |
60943 | 1047 |
| _ => (*G admits some unsafe rules: try later*) |
1048 |
(cond_tracing trace (fn () => "moving formula to unsafe list"); |
|
42804 | 1049 |
prv (if isGoal G then negOfGoal_tac ctxt :: tacs |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1050 |
else tacs, |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1051 |
brs0::trs, |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1052 |
choices, |
60943 | 1053 |
{pairs = (br, unsafe@[(negOfGoal G, md)])::pairs, |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1054 |
lits = lits, |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1055 |
vars = vars, |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1056 |
lim = lim} :: brs))) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1057 |
end |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1058 |
| prv (tacs, trs, choices, |
60943 | 1059 |
{pairs = ([],unsafe)::(Gs,unsafe')::pairs, lits, vars, lim} :: brs) = |
1060 |
(*no more "safe" formulae: transfer unsafe down a level*) |
|
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1061 |
prv (tacs, trs, choices, |
60943 | 1062 |
{pairs = (Gs,unsafe@unsafe')::pairs, |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1063 |
lits = lits, |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1064 |
vars = vars, |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1065 |
lim = lim} :: brs) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1066 |
| prv (tacs, trs, choices, |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1067 |
brs0 as {pairs = [([], (H,md)::Hs)], |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1068 |
lits, vars, lim} :: brs) = |
60943 | 1069 |
(*no safe steps possible at any level: apply a unsafe rule*) |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1070 |
let exception PRV (*backtrack to precisely this recursion!*) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1071 |
val H = norm H |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1072 |
val ntrl = !ntrail |
60943 | 1073 |
val rules = netMkRules state H vars unsafeList |
1074 |
(*new premises of unsafe rules may NOT be duplicated*) |
|
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1075 |
fun newPrem (vars,P,dup,lim') prem = |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1076 |
let val Gs' = map (fn Q => (Q,false)) prem |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1077 |
and Hs' = if dup then Hs @ [(negOfGoal H, md)] else Hs |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1078 |
and lits' = if (exists isGoal prem) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1079 |
then map negOfGoal lits |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1080 |
else lits |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1081 |
in {pairs = if exists (match P) prem then [(Gs',Hs')] |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1082 |
(*Recursive in this premise. Don't make new |
60943 | 1083 |
"stack frame". New unsafe premises will end up |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1084 |
at the BACK of the queue, preventing |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1085 |
exclusion of others*) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1086 |
else [(Gs',[]), ([],Hs')], |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1087 |
lits = lits', |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1088 |
vars = vars, |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1089 |
lim = lim'} |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1090 |
end |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1091 |
fun newBr x prems = map (newPrem x) prems @ brs |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1092 |
(*Seek a matching rule. If unifiable then add new premises |
2854 | 1093 |
to branch.*) |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1094 |
fun deeper [] = raise NEWBRANCHES |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1095 |
| deeper (((P,prems),tac)::grls) = |
24062
845c0d693328
explicit global state argument -- no longer CRITICAL;
wenzelm
parents:
23985
diff
changeset
|
1096 |
if unify state (add_term_vars(P,[]), P, H) |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1097 |
then |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1098 |
let val updated = ntrl < !ntrail (*branch updated*) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1099 |
val vars = vars_in_vars vars |
30190 | 1100 |
val vars' = List.foldr add_terms_vars vars prems |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1101 |
(*duplicate H if md permits*) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1102 |
val dup = md (*earlier had "andalso vars' <> vars": |
11152
32d002362005
Blast bug fix: now always duplicates when applying a haz rule,
paulson
parents:
11119
diff
changeset
|
1103 |
duplicate only if the subgoal has new vars*) |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1104 |
(*any instances of P in the subgoals? |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1105 |
NB: boolean "recur" affects tracing only!*) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1106 |
and recur = exists (exists (match P)) prems |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1107 |
val lim' = (*Decrement "lim" extra if updates occur*) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1108 |
if updated then lim - (1+log(length rules)) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1109 |
else lim-1 |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1110 |
(*It is tempting to leave "lim" UNCHANGED if |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1111 |
both dup and recur are false. Proofs are |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1112 |
found at shallower depths, but looping |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1113 |
occurs too often...*) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1114 |
val mayUndo = |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1115 |
(*Allowing backtracking from a rule application |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1116 |
if other matching rules exist, if the rule |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1117 |
updated variables, or if the rule did not |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1118 |
introduce new variables. This latter condition |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1119 |
means it is not a standard "gamma-rule" but |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1120 |
some other form of unsafe rule. Aim is to |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1121 |
emulate Fast_tac, which allows all unsafe steps |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1122 |
to be undone.*) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1123 |
not(null grls) (*other rules to try?*) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1124 |
orelse updated |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1125 |
orelse vars=vars' (*no new Vars?*) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1126 |
val tac' = tac(updated, dup, true) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1127 |
(*if recur then perhaps shouldn't call rotate_tac: new |
5463
a5479f5cd482
Allows more backtracking in proof reconstruction, making it slower but more
paulson
parents:
5411
diff
changeset
|
1128 |
formulae should be last, but that's WRONG if the new |
a5479f5cd482
Allows more backtracking in proof reconstruction, making it slower but more
paulson
parents:
5411
diff
changeset
|
1129 |
formulae are Goals, since they remain in the first |
a5479f5cd482
Allows more backtracking in proof reconstruction, making it slower but more
paulson
parents:
5411
diff
changeset
|
1130 |
position*) |
a5479f5cd482
Allows more backtracking in proof reconstruction, making it slower but more
paulson
parents:
5411
diff
changeset
|
1131 |
|
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1132 |
in |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1133 |
if lim'<0 andalso not (null prems) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1134 |
then (*it's faster to kill ALL the alternatives*) |
54942
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
1135 |
(cond_tracing trace (fn () => "Excessive branching: KILLED"); |
24062
845c0d693328
explicit global state argument -- no longer CRITICAL;
wenzelm
parents:
23985
diff
changeset
|
1136 |
clearTo state ntrl; raise NEWBRANCHES) |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1137 |
else |
42804 | 1138 |
traceNew trace prems; |
54942
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
1139 |
cond_tracing (trace andalso dup) (fn () => " (duplicating)"); |
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
1140 |
cond_tracing (trace andalso recur) (fn () => " (recursive)"); |
24062
845c0d693328
explicit global state argument -- no longer CRITICAL;
wenzelm
parents:
23985
diff
changeset
|
1141 |
traceVars state ntrl; |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1142 |
if null prems then nclosed := !nclosed + 1 |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1143 |
else ntried := !ntried + length prems - 1; |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1144 |
prv(tac' :: tacs, |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1145 |
brs0::trs, |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1146 |
(ntrl, length brs0, PRV) :: choices, |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1147 |
newBr (vars', P, dup, lim') prems) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1148 |
handle PRV => |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1149 |
if mayUndo |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1150 |
then (*reset Vars and try another rule*) |
24062
845c0d693328
explicit global state argument -- no longer CRITICAL;
wenzelm
parents:
23985
diff
changeset
|
1151 |
(clearTo state ntrl; deeper grls) |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1152 |
else (*backtrack to previous level*) |
42804 | 1153 |
backtrack trace choices |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1154 |
end |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1155 |
else deeper grls |
54942
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
1156 |
in |
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
1157 |
trace_prover state brs0; |
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
1158 |
if lim<1 then (cond_tracing trace (fn () => "Limit reached."); backtrack trace choices) |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1159 |
else deeper rules |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1160 |
handle NEWBRANCHES => |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1161 |
(*cannot close branch: move H to literals*) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1162 |
prv (tacs, brs0::trs, choices, |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1163 |
{pairs = [([], Hs)], |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1164 |
lits = H::lits, |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1165 |
vars = vars, |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1166 |
lim = lim} :: brs) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1167 |
end |
42804 | 1168 |
| prv (tacs, trs, choices, _ :: brs) = backtrack trace choices |
12346 | 1169 |
in prv ([], [], [(!ntrail, length brs, PROVE)], brs) end; |
2854 | 1170 |
|
1171 |
||
2883 | 1172 |
(*Construct an initial branch.*) |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1173 |
fun initBranch (ts,lim) = |
5463
a5479f5cd482
Allows more backtracking in proof reconstruction, making it slower but more
paulson
parents:
5411
diff
changeset
|
1174 |
{pairs = [(map (fn t => (t,true)) ts, [])], |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1175 |
lits = [], |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1176 |
vars = add_terms_vars (ts,[]), |
5463
a5479f5cd482
Allows more backtracking in proof reconstruction, making it slower but more
paulson
parents:
5411
diff
changeset
|
1177 |
lim = lim}; |
2854 | 1178 |
|
1179 |
||
1180 |
(*** Conversion & Skolemization of the Isabelle proof state ***) |
|
1181 |
||
1182 |
(*Make a list of all the parameters in a subgoal, even if nested*) |
|
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1183 |
local open Term |
2854 | 1184 |
in |
56245 | 1185 |
fun discard_foralls (Const(@{const_name Pure.all},_)$Abs(a,T,t)) = discard_foralls t |
2854 | 1186 |
| discard_foralls t = t; |
1187 |
end; |
|
1188 |
||
1189 |
(*List of variables not appearing as arguments to the given parameter*) |
|
1190 |
fun getVars [] i = [] |
|
20664 | 1191 |
| getVars ((_,(v,is))::alist) (i: int) = |
1192 |
if member (op =) is i then getVars alist i |
|
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1193 |
else v :: getVars alist i; |
2854 | 1194 |
|
4233
85d004a96b98
Rationalized error handling: if low-level tactic (depth_tac) cannot accept the
paulson
parents:
4196
diff
changeset
|
1195 |
exception TRANS of string; |
2854 | 1196 |
|
4233
85d004a96b98
Rationalized error handling: if low-level tactic (depth_tac) cannot accept the
paulson
parents:
4196
diff
changeset
|
1197 |
(*Translation of a subgoal: Skolemize all parameters*) |
43349 | 1198 |
fun fromSubgoal (state as State {ctxt, ...}) t = |
1199 |
let val thy = Proof_Context.theory_of ctxt |
|
1200 |
val alistVar = Unsynchronized.ref [] |
|
32740 | 1201 |
and alistTVar = Unsynchronized.ref [] |
2854 | 1202 |
fun hdvar ((ix,(v,is))::_) = v |
1203 |
fun from lev t = |
|
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1204 |
let val (ht,ts) = Term.strip_comb t |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1205 |
fun apply u = list_comb (u, map (from lev) ts) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1206 |
fun bounds [] = [] |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1207 |
| bounds (Term.Bound i::ts) = |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1208 |
if i<lev then raise TRANS |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1209 |
"Function unknown's argument not a parameter" |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1210 |
else i-lev :: bounds ts |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1211 |
| bounds ts = raise TRANS |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1212 |
"Function unknown's argument not a bound variable" |
2854 | 1213 |
in |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1214 |
case ht of |
24062
845c0d693328
explicit global state argument -- no longer CRITICAL;
wenzelm
parents:
23985
diff
changeset
|
1215 |
Term.Const aT => apply (fromConst thy alistTVar aT) |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1216 |
| Term.Free (a,_) => apply (Free a) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1217 |
| Term.Bound i => apply (Bound i) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1218 |
| Term.Var (ix,_) => |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1219 |
(case (AList.lookup (op =) (!alistVar) ix) of |
32740 | 1220 |
NONE => (alistVar := (ix, (Unsynchronized.ref NONE, bounds ts)) |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1221 |
:: !alistVar; |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1222 |
Var (hdvar(!alistVar))) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1223 |
| SOME(v,is) => if is=bounds ts then Var v |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1224 |
else raise TRANS |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1225 |
("Discrepancy among occurrences of " |
22678 | 1226 |
^ Term.string_of_vname ix)) |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1227 |
| Term.Abs (a,_,body) => |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1228 |
if null ts then Abs(a, from (lev+1) body) |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1229 |
else raise TRANS "argument not in normal form" |
2854 | 1230 |
end |
1231 |
||
1232 |
val npars = length (Logic.strip_params t) |
|
1233 |
||
1234 |
(*Skolemize a subgoal from a proof state*) |
|
1235 |
fun skoSubgoal i t = |
|
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1236 |
if i<npars then |
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1237 |
skoSubgoal (i+1) |
43349 | 1238 |
(subst_bound (Skolem (gensym state "T", getVars (!alistVar) i), t)) |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1239 |
else t |
2854 | 1240 |
|
1241 |
in skoSubgoal 0 (from 0 (discard_foralls t)) end; |
|
1242 |
||
1243 |
||
43331
01f051619eee
clarified raw_blast, which is not really a tactic since it operates directly on subgoal 1 without bounds check (cf. c46107e6714b);
wenzelm
parents:
43045
diff
changeset
|
1244 |
(*Tableau engine and proof reconstruction operating on subgoal 1. |
01f051619eee
clarified raw_blast, which is not really a tactic since it operates directly on subgoal 1 without bounds check (cf. c46107e6714b);
wenzelm
parents:
43045
diff
changeset
|
1245 |
"start" is CPU time at start, for printing SEARCH time (also prints reconstruction time) |
2854 | 1246 |
"lim" is depth limit.*) |
43331
01f051619eee
clarified raw_blast, which is not really a tactic since it operates directly on subgoal 1 without bounds check (cf. c46107e6714b);
wenzelm
parents:
43045
diff
changeset
|
1247 |
fun raw_blast start ctxt lim st = |
43349 | 1248 |
let val state = initialize ctxt |
42804 | 1249 |
val trace = Config.get ctxt trace; |
1250 |
val stats = Config.get ctxt stats; |
|
43349 | 1251 |
val skoprem = fromSubgoal state (#1 (Logic.dest_implies (Thm.prop_of st))) |
4323
561242f8606b
Printing of statistics including time for search & reconstruction
paulson
parents:
4300
diff
changeset
|
1252 |
val hyps = strip_imp_prems skoprem |
561242f8606b
Printing of statistics including time for search & reconstruction
paulson
parents:
4300
diff
changeset
|
1253 |
and concl = strip_imp_concl skoprem |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1254 |
fun cont (tacs,_,choices) = |
42012
2c3fe3cbebae
structure Timing: covers former start_timing/end_timing and Output.timeit etc;
wenzelm
parents:
41491
diff
changeset
|
1255 |
let val start = Timing.start () |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1256 |
in |
42369 | 1257 |
case Seq.pull(EVERY' (rev tacs) 1 st) of |
54942
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
1258 |
NONE => (cond_tracing trace (fn () => "PROOF FAILED for depth " ^ string_of_int lim); |
42804 | 1259 |
backtrack trace choices) |
54942
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
1260 |
| cell => (cond_tracing (trace orelse stats) |
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
1261 |
(fn () => Timing.message (Timing.result start) ^ " for reconstruction"); |
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1262 |
Seq.make(fn()=> cell)) |
4323
561242f8606b
Printing of statistics including time for search & reconstruction
paulson
parents:
4300
diff
changeset
|
1263 |
end |
42369 | 1264 |
in |
42801
da4ad5f98953
proper Proof.context -- eliminated global operations;
wenzelm
parents:
42793
diff
changeset
|
1265 |
prove (state, start, [initBranch (mkGoal concl :: hyps, lim)], cont) |
42369 | 1266 |
end |
43331
01f051619eee
clarified raw_blast, which is not really a tactic since it operates directly on subgoal 1 without bounds check (cf. c46107e6714b);
wenzelm
parents:
43045
diff
changeset
|
1267 |
handle PROVE => Seq.empty |
54942
ed36358c20d5
uniform output of tracing via official channel (usually depending on trace flag);
wenzelm
parents:
54897
diff
changeset
|
1268 |
| TRANS s => (cond_tracing (Config.get ctxt trace) (fn () => "Blast: " ^ s); Seq.empty); |
2854 | 1269 |
|
43331
01f051619eee
clarified raw_blast, which is not really a tactic since it operates directly on subgoal 1 without bounds check (cf. c46107e6714b);
wenzelm
parents:
43045
diff
changeset
|
1270 |
fun depth_tac ctxt lim i st = |
01f051619eee
clarified raw_blast, which is not really a tactic since it operates directly on subgoal 1 without bounds check (cf. c46107e6714b);
wenzelm
parents:
43045
diff
changeset
|
1271 |
SELECT_GOAL |
54742
7a86358a3c0b
proper context for basic Simplifier operations: rewrite_rule, rewrite_goals_rule, rewrite_goals_tac etc.;
wenzelm
parents:
53536
diff
changeset
|
1272 |
(Object_Logic.atomize_prems_tac ctxt 1 THEN |
43331
01f051619eee
clarified raw_blast, which is not really a tactic since it operates directly on subgoal 1 without bounds check (cf. c46107e6714b);
wenzelm
parents:
43045
diff
changeset
|
1273 |
raw_blast (Timing.start ()) ctxt lim) i st; |
01f051619eee
clarified raw_blast, which is not really a tactic since it operates directly on subgoal 1 without bounds check (cf. c46107e6714b);
wenzelm
parents:
43045
diff
changeset
|
1274 |
|
42793 | 1275 |
fun blast_tac ctxt i st = |
43331
01f051619eee
clarified raw_blast, which is not really a tactic since it operates directly on subgoal 1 without bounds check (cf. c46107e6714b);
wenzelm
parents:
43045
diff
changeset
|
1276 |
let |
01f051619eee
clarified raw_blast, which is not really a tactic since it operates directly on subgoal 1 without bounds check (cf. c46107e6714b);
wenzelm
parents:
43045
diff
changeset
|
1277 |
val start = Timing.start (); |
01f051619eee
clarified raw_blast, which is not really a tactic since it operates directly on subgoal 1 without bounds check (cf. c46107e6714b);
wenzelm
parents:
43045
diff
changeset
|
1278 |
val lim = Config.get ctxt depth_limit; |
01f051619eee
clarified raw_blast, which is not really a tactic since it operates directly on subgoal 1 without bounds check (cf. c46107e6714b);
wenzelm
parents:
43045
diff
changeset
|
1279 |
in |
01f051619eee
clarified raw_blast, which is not really a tactic since it operates directly on subgoal 1 without bounds check (cf. c46107e6714b);
wenzelm
parents:
43045
diff
changeset
|
1280 |
SELECT_GOAL |
54742
7a86358a3c0b
proper context for basic Simplifier operations: rewrite_rule, rewrite_goals_rule, rewrite_goals_tac etc.;
wenzelm
parents:
53536
diff
changeset
|
1281 |
(Object_Logic.atomize_prems_tac ctxt 1 THEN |
43348 | 1282 |
DEEPEN (1, lim) (fn m => fn _ => raw_blast start ctxt m) 0 1) i st |
43331
01f051619eee
clarified raw_blast, which is not really a tactic since it operates directly on subgoal 1 without bounds check (cf. c46107e6714b);
wenzelm
parents:
43045
diff
changeset
|
1283 |
end; |
2854 | 1284 |
|
1285 |
||
2924
af506c35b4ed
Control over excessive branching by applying a log2 penalty
paulson
parents:
2894
diff
changeset
|
1286 |
|
18525
ce1ae48c320f
avoid implicit assumptions about consts Not, op =, *Goal*, *False*;
wenzelm
parents:
18177
diff
changeset
|
1287 |
(*** For debugging: these apply the prover to a subgoal and return |
2924
af506c35b4ed
Control over excessive branching by applying a log2 penalty
paulson
parents:
2894
diff
changeset
|
1288 |
the resulting tactics, trace, etc. ***) |
af506c35b4ed
Control over excessive branching by applying a log2 penalty
paulson
parents:
2894
diff
changeset
|
1289 |
|
af506c35b4ed
Control over excessive branching by applying a log2 penalty
paulson
parents:
2894
diff
changeset
|
1290 |
(*Read a string to make an initial, singleton branch*) |
42793 | 1291 |
fun readGoal ctxt s = |
1292 |
Syntax.read_prop ctxt s |> fromTerm (Proof_Context.theory_of ctxt) |> rand |> mkGoal; |
|
2924
af506c35b4ed
Control over excessive branching by applying a log2 penalty
paulson
parents:
2894
diff
changeset
|
1293 |
|
42793 | 1294 |
fun tryIt ctxt lim s = |
24062
845c0d693328
explicit global state argument -- no longer CRITICAL;
wenzelm
parents:
23985
diff
changeset
|
1295 |
let |
42804 | 1296 |
val state as State {fullTrace, ...} = initialize ctxt; |
42801
da4ad5f98953
proper Proof.context -- eliminated global operations;
wenzelm
parents:
42793
diff
changeset
|
1297 |
val res = timeap prove (state, Timing.start (), [initBranch ([readGoal ctxt s], lim)], I); |
42804 | 1298 |
in {fullTrace = !fullTrace, result = res} end; |
2924
af506c35b4ed
Control over excessive branching by applying a log2 penalty
paulson
parents:
2894
diff
changeset
|
1299 |
|
af506c35b4ed
Control over excessive branching by applying a log2 penalty
paulson
parents:
2894
diff
changeset
|
1300 |
|
58826 | 1301 |
|
5926 | 1302 |
(** method setup **) |
1303 |
||
58826 | 1304 |
val _ = |
1305 |
Theory.setup |
|
1306 |
(Method.setup @{binding blast} |
|
1307 |
(Scan.lift (Scan.option Parse.nat) --| Method.sections Classical.cla_modifiers >> |
|
1308 |
(fn NONE => SIMPLE_METHOD' o blast_tac |
|
1309 |
| SOME lim => (fn ctxt => SIMPLE_METHOD' (depth_tac ctxt lim)))) |
|
1310 |
"classical tableau prover"); |
|
5926 | 1311 |
|
2854 | 1312 |
end; |