src/HOL/UNITY/UNITY_tactics.ML
author kuncar
Fri Dec 09 18:07:04 2011 +0100 (2011-12-09)
changeset 45802 b16f976db515
parent 45138 ba618e9288b8
child 46752 e9e7209eb375
permissions -rw-r--r--
Quotient_Info stores only relation maps
     1 (*  Title:      HOL/UNITY/UNITY_tactics.ML
     2     Author:     Lawrence C Paulson, Cambridge University Computer Laboratory
     3     Copyright   2003  University of Cambridge
     4 
     5 Specialized UNITY tactics.
     6 *)
     7 
     8 (*Combines two invariance ASSUMPTIONS into one.  USEFUL??*)
     9 val Always_Int_tac = dtac @{thm Always_Int_I} THEN' assume_tac THEN' etac @{thm Always_thin}
    10 
    11 (*Combines a list of invariance THEOREMS into one.*)
    12 val Always_Int_rule = foldr1 (fn (th1,th2) => [th1,th2] MRS @{thm Always_Int_I})
    13 
    14 (*Proves "co" properties when the program is specified.  Any use of invariants
    15   (from weak constrains) must have been done already.*)
    16 fun constrains_tac ctxt i =
    17   SELECT_GOAL
    18     (EVERY
    19      [REPEAT (Always_Int_tac 1),
    20       (*reduce the fancy safety properties to "constrains"*)
    21       REPEAT (etac @{thm Always_ConstrainsI} 1
    22               ORELSE
    23               resolve_tac [@{thm StableI}, @{thm stableI},
    24                            @{thm constrains_imp_Constrains}] 1),
    25       (*for safety, the totalize operator can be ignored*)
    26       simp_tac (HOL_ss addsimps [@{thm mk_total_program_def}, @{thm totalize_constrains_iff}]) 1,
    27       rtac @{thm constrainsI} 1,
    28       full_simp_tac (simpset_of ctxt) 1,
    29       REPEAT (FIRSTGOAL (etac disjE)),
    30       ALLGOALS (clarify_tac ctxt),
    31       ALLGOALS (asm_full_simp_tac (simpset_of ctxt))]) i;
    32 
    33 (*proves "ensures/leadsTo" properties when the program is specified*)
    34 fun ensures_tac ctxt sact =
    35   SELECT_GOAL
    36     (EVERY
    37      [REPEAT (Always_Int_tac 1),
    38       etac @{thm Always_LeadsTo_Basis} 1
    39           ORELSE   (*subgoal may involve LeadsTo, leadsTo or ensures*)
    40           REPEAT (ares_tac [@{thm LeadsTo_Basis}, @{thm leadsTo_Basis},
    41                             @{thm EnsuresI}, @{thm ensuresI}] 1),
    42       (*now there are two subgoals: co & transient*)
    43       simp_tac (simpset_of ctxt addsimps [@{thm mk_total_program_def}]) 2,
    44       res_inst_tac ctxt
    45         [(("act", 0), sact)] @{thm totalize_transientI} 2
    46       ORELSE res_inst_tac ctxt
    47         [(("act", 0), sact)] @{thm transientI} 2,
    48          (*simplify the command's domain*)
    49       simp_tac (simpset_of ctxt addsimps @{thms Domain_def}) 3,
    50       constrains_tac ctxt 1,
    51       ALLGOALS (clarify_tac ctxt),
    52       ALLGOALS (asm_lr_simp_tac (simpset_of ctxt))]);
    53 
    54 
    55 (*Composition equivalences, from Lift_prog*)
    56 
    57 fun make_o_equivs th =
    58     [th,
    59      th RS @{thm o_equiv_assoc} |> simplify (HOL_ss addsimps [@{thm o_assoc}]),
    60      th RS @{thm o_equiv_apply} |> simplify (HOL_ss addsimps [@{thm o_def}, @{thm sub_def}])];
    61