Theory Sequents

(*  Title:      Sequents/Sequents.thy
    Author:     Lawrence C Paulson, Cambridge University Computer Laboratory
    Copyright   1993  University of Cambridge
*)

section ‹Parsing and pretty-printing of sequences›

theory Sequents
imports Pure
keywords "print_pack" :: diag
begin

setup Pure_Thy.old_appl_syntax_setup

declare [[unify_trace_bound = 20, unify_search_bound = 40]]

typedecl o


subsection ‹Sequences›

typedecl seq'
consts
 SeqO'         :: "[o,seq']seq'"
 Seq1'         :: "oseq'"


subsection ‹Concrete syntax›

nonterminal seq and seqobj and seqcont

syntax
 "_SeqEmp"         :: seq                                  ("")
 "_SeqApp"         :: "[seqobj,seqcont]  seq"            ("__")

 "_SeqContEmp"     :: seqcont                              ("")
 "_SeqContApp"     :: "[seqobj,seqcont]  seqcont"        (",/ __")

 "_SeqO"           :: "o  seqobj"                        ("_")
 "_SeqId"          :: "'a  seqobj"                       ("$_")

type_synonym single_seqe = "[seq,seqobj]  prop"
type_synonym single_seqi = "[seq'seq',seq'seq']  prop"
type_synonym two_seqi = "[seq'seq', seq'seq']  prop"
type_synonym two_seqe = "[seq, seq]  prop"
type_synonym three_seqi = "[seq'seq', seq'seq', seq'seq']  prop"
type_synonym three_seqe = "[seq, seq, seq]  prop"
type_synonym four_seqi = "[seq'seq', seq'seq', seq'seq', seq'seq']  prop"
type_synonym four_seqe = "[seq, seq, seq, seq]  prop"
type_synonym sequence_name = "seq'seq'"


syntax
  (*Constant to allow definitions of SEQUENCES of formulas*)
  "_Side"        :: "seq(seq'seq')"     ("<<(_)>>")

ML (* parse translation for sequences *)

fun abs_seq' t = Abs ("s", Typeseq', t);

fun seqobj_tr (Const (syntax_const‹_SeqO›, _) $ f) = Syntax.const const_syntaxSeqO' $ f
  | seqobj_tr (_ $ i) = i;

fun seqcont_tr (Const (syntax_const‹_SeqContEmp›, _)) = Bound 0
  | seqcont_tr (Const (syntax_const‹_SeqContApp›, _) $ so $ sc) =
      seqobj_tr so $ seqcont_tr sc;

fun seq_tr (Const (syntax_const‹_SeqEmp›, _)) = abs_seq' (Bound 0)
  | seq_tr (Const (syntax_const‹_SeqApp›, _) $ so $ sc) =
      abs_seq'(seqobj_tr so $ seqcont_tr sc);

fun singlobj_tr (Const (syntax_const‹_SeqO›,_) $ f) =
  abs_seq' ((Syntax.const const_syntaxSeqO' $ f) $ Bound 0);


(* print translation for sequences *)

fun seqcont_tr' (Bound 0) = Syntax.const syntax_const‹_SeqContEmp›
  | seqcont_tr' (Const (const_syntaxSeqO', _) $ f $ s) =
      Syntax.const syntax_const‹_SeqContApp› $
        (Syntax.const syntax_const‹_SeqO› $ f) $ seqcont_tr' s
  | seqcont_tr' (i $ s) =
      Syntax.const syntax_const‹_SeqContApp› $
        (Syntax.const syntax_const‹_SeqId› $ i) $ seqcont_tr' s;

fun seq_tr' s =
  let
    fun seq_itr' (Bound 0) = Syntax.const syntax_const‹_SeqEmp›
      | seq_itr' (Const (const_syntaxSeqO', _) $ f $ s) =
          Syntax.const syntax_const‹_SeqApp› $
            (Syntax.const syntax_const‹_SeqO› $ f) $ seqcont_tr' s
      | seq_itr' (i $ s) =
          Syntax.const syntax_const‹_SeqApp› $
            (Syntax.const syntax_const‹_SeqId› $ i) $ seqcont_tr' s
  in
    case s of
      Abs (_, _, t) => seq_itr' t
    | _ => s $ Bound 0
  end;


fun single_tr c [s1, s2] =
  Syntax.const c $ seq_tr s1 $ singlobj_tr s2;

fun two_seq_tr c [s1, s2] =
  Syntax.const c $ seq_tr s1 $ seq_tr s2;

fun three_seq_tr c [s1, s2, s3] =
  Syntax.const c $ seq_tr s1 $ seq_tr s2 $ seq_tr s3;

fun four_seq_tr c [s1, s2, s3, s4] =
  Syntax.const c $ seq_tr s1 $ seq_tr s2 $ seq_tr s3 $ seq_tr s4;


fun singlobj_tr' (Const (const_syntaxSeqO',_) $ fm) = fm
  | singlobj_tr' id = Syntax.const syntax_const‹_SeqId› $ id;


fun single_tr' c [s1, s2] =
  Syntax.const c $ seq_tr' s1 $ seq_tr' s2;

fun two_seq_tr' c [s1, s2] =
  Syntax.const c $ seq_tr' s1 $ seq_tr' s2;

fun three_seq_tr' c [s1, s2, s3] =
  Syntax.const c $ seq_tr' s1 $ seq_tr' s2 $ seq_tr' s3;

fun four_seq_tr' c [s1, s2, s3, s4] =
  Syntax.const c $ seq_tr' s1 $ seq_tr' s2 $ seq_tr' s3 $ seq_tr' s4;



(** for the <<...>> notation **)

fun side_tr [s1] = seq_tr s1;

parse_translation [(syntax_const‹_Side›, K side_tr)]


subsection ‹Proof tools›

ML_file ‹prover.ML›

end