src/HOL/Set.thy
author paulson
Mon Mar 17 17:37:20 2003 +0100 (2003-03-17)
changeset 13865 0a6bf71955b0
parent 13860 b681a3cb0beb
child 14098 54f130df1136
permissions -rw-r--r--
moved one proof, added another
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(*  Title:      HOL/Set.thy
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    ID:         $Id$
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    Author:     Tobias Nipkow, Lawrence C Paulson and Markus Wenzel
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    License:    GPL (GNU GENERAL PUBLIC LICENSE)
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*)
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header {* Set theory for higher-order logic *}
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theory Set = HOL:
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text {* A set in HOL is simply a predicate. *}
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subsection {* Basic syntax *}
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global
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typedecl 'a set
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arities set :: (type) type
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consts
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  "{}"          :: "'a set"                             ("{}")
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  UNIV          :: "'a set"
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  insert        :: "'a => 'a set => 'a set"
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  Collect       :: "('a => bool) => 'a set"              -- "comprehension"
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  Int           :: "'a set => 'a set => 'a set"          (infixl 70)
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  Un            :: "'a set => 'a set => 'a set"          (infixl 65)
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  UNION         :: "'a set => ('a => 'b set) => 'b set"  -- "general union"
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  INTER         :: "'a set => ('a => 'b set) => 'b set"  -- "general intersection"
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  Union         :: "'a set set => 'a set"                -- "union of a set"
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  Inter         :: "'a set set => 'a set"                -- "intersection of a set"
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  Pow           :: "'a set => 'a set set"                -- "powerset"
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  Ball          :: "'a set => ('a => bool) => bool"      -- "bounded universal quantifiers"
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  Bex           :: "'a set => ('a => bool) => bool"      -- "bounded existential quantifiers"
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  image         :: "('a => 'b) => 'a set => 'b set"      (infixr "`" 90)
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syntax
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  "op :"        :: "'a => 'a set => bool"                ("op :")
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consts
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  "op :"        :: "'a => 'a set => bool"                ("(_/ : _)" [50, 51] 50)  -- "membership"
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local
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instance set :: (type) ord ..
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instance set :: (type) minus ..
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subsection {* Additional concrete syntax *}
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syntax
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  range         :: "('a => 'b) => 'b set"             -- "of function"
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  "op ~:"       :: "'a => 'a set => bool"                 ("op ~:")  -- "non-membership"
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  "op ~:"       :: "'a => 'a set => bool"                 ("(_/ ~: _)" [50, 51] 50)
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  "@Finset"     :: "args => 'a set"                       ("{(_)}")
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  "@Coll"       :: "pttrn => bool => 'a set"              ("(1{_./ _})")
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  "@SetCompr"   :: "'a => idts => bool => 'a set"         ("(1{_ |/_./ _})")
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  "@INTER1"     :: "pttrns => 'b set => 'b set"           ("(3INT _./ _)" 10)
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  "@UNION1"     :: "pttrns => 'b set => 'b set"           ("(3UN _./ _)" 10)
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  "@INTER"      :: "pttrn => 'a set => 'b set => 'b set"  ("(3INT _:_./ _)" 10)
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  "@UNION"      :: "pttrn => 'a set => 'b set => 'b set"  ("(3UN _:_./ _)" 10)
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  "_Ball"       :: "pttrn => 'a set => bool => bool"      ("(3ALL _:_./ _)" [0, 0, 10] 10)
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  "_Bex"        :: "pttrn => 'a set => bool => bool"      ("(3EX _:_./ _)" [0, 0, 10] 10)
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syntax (HOL)
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  "_Ball"       :: "pttrn => 'a set => bool => bool"      ("(3! _:_./ _)" [0, 0, 10] 10)
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  "_Bex"        :: "pttrn => 'a set => bool => bool"      ("(3? _:_./ _)" [0, 0, 10] 10)
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translations
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  "range f"     == "f`UNIV"
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  "x ~: y"      == "~ (x : y)"
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  "{x, xs}"     == "insert x {xs}"
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  "{x}"         == "insert x {}"
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  "{x. P}"      == "Collect (%x. P)"
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  "UN x y. B"   == "UN x. UN y. B"
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  "UN x. B"     == "UNION UNIV (%x. B)"
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  "UN x. B"     == "UN x:UNIV. B"
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  "INT x y. B"  == "INT x. INT y. B"
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  "INT x. B"    == "INTER UNIV (%x. B)"
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  "INT x. B"    == "INT x:UNIV. B"
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  "UN x:A. B"   == "UNION A (%x. B)"
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  "INT x:A. B"  == "INTER A (%x. B)"
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  "ALL x:A. P"  == "Ball A (%x. P)"
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  "EX x:A. P"   == "Bex A (%x. P)"
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syntax (output)
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  "_setle"      :: "'a set => 'a set => bool"             ("op <=")
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  "_setle"      :: "'a set => 'a set => bool"             ("(_/ <= _)" [50, 51] 50)
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  "_setless"    :: "'a set => 'a set => bool"             ("op <")
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  "_setless"    :: "'a set => 'a set => bool"             ("(_/ < _)" [50, 51] 50)
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syntax (xsymbols)
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  "_setle"      :: "'a set => 'a set => bool"             ("op \<subseteq>")
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  "_setle"      :: "'a set => 'a set => bool"             ("(_/ \<subseteq> _)" [50, 51] 50)
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  "_setless"    :: "'a set => 'a set => bool"             ("op \<subset>")
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  "_setless"    :: "'a set => 'a set => bool"             ("(_/ \<subset> _)" [50, 51] 50)
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  "op Int"      :: "'a set => 'a set => 'a set"           (infixl "\<inter>" 70)
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  "op Un"       :: "'a set => 'a set => 'a set"           (infixl "\<union>" 65)
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  "op :"        :: "'a => 'a set => bool"                 ("op \<in>")
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  "op :"        :: "'a => 'a set => bool"                 ("(_/ \<in> _)" [50, 51] 50)
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  "op ~:"       :: "'a => 'a set => bool"                 ("op \<notin>")
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  "op ~:"       :: "'a => 'a set => bool"                 ("(_/ \<notin> _)" [50, 51] 50)
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  "@UNION1"     :: "pttrns => 'b set => 'b set"           ("(3\<Union>_./ _)" 10)
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  "@INTER1"     :: "pttrns => 'b set => 'b set"           ("(3\<Inter>_./ _)" 10)
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  "@UNION"      :: "pttrn => 'a set => 'b set => 'b set"  ("(3\<Union>_\<in>_./ _)" 10)
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  "@INTER"      :: "pttrn => 'a set => 'b set => 'b set"  ("(3\<Inter>_\<in>_./ _)" 10)
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  Union         :: "'a set set => 'a set"                 ("\<Union>_" [90] 90)
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  Inter         :: "'a set set => 'a set"                 ("\<Inter>_" [90] 90)
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  "_Ball"       :: "pttrn => 'a set => bool => bool"      ("(3\<forall>_\<in>_./ _)" [0, 0, 10] 10)
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  "_Bex"        :: "pttrn => 'a set => bool => bool"      ("(3\<exists>_\<in>_./ _)" [0, 0, 10] 10)
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translations
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  "op \<subseteq>" => "op <= :: _ set => _ set => bool"
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  "op \<subset>" => "op <  :: _ set => _ set => bool"
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typed_print_translation {*
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  let
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    fun le_tr' _ (Type ("fun", (Type ("set", _) :: _))) ts =
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          list_comb (Syntax.const "_setle", ts)
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      | le_tr' _ _ _ = raise Match;
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    fun less_tr' _ (Type ("fun", (Type ("set", _) :: _))) ts =
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          list_comb (Syntax.const "_setless", ts)
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      | less_tr' _ _ _ = raise Match;
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  in [("op <=", le_tr'), ("op <", less_tr')] end
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*}
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text {*
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  \medskip Translate between @{text "{e | x1...xn. P}"} and @{text
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  "{u. EX x1..xn. u = e & P}"}; @{text "{y. EX x1..xn. y = e & P}"} is
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  only translated if @{text "[0..n] subset bvs(e)"}.
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*}
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parse_translation {*
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  let
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    val ex_tr = snd (mk_binder_tr ("EX ", "Ex"));
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    fun nvars (Const ("_idts", _) $ _ $ idts) = nvars idts + 1
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      | nvars _ = 1;
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    fun setcompr_tr [e, idts, b] =
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      let
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        val eq = Syntax.const "op =" $ Bound (nvars idts) $ e;
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        val P = Syntax.const "op &" $ eq $ b;
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        val exP = ex_tr [idts, P];
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      in Syntax.const "Collect" $ Abs ("", dummyT, exP) end;
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  in [("@SetCompr", setcompr_tr)] end;
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*}
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(* To avoid eta-contraction of body: *)
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print_translation {*
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let
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  fun btr' syn [A,Abs abs] =
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    let val (x,t) = atomic_abs_tr' abs
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    in Syntax.const syn $ x $ A $ t end
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in
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[("Ball", btr' "_Ball"),("Bex", btr' "_Bex"),
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 ("UNION", btr' "@UNION"),("INTER", btr' "@INTER")]
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end
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*}
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print_translation {*
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let
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  val ex_tr' = snd (mk_binder_tr' ("Ex", "DUMMY"));
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  fun setcompr_tr' [Abs (abs as (_, _, P))] =
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    let
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      fun check (Const ("Ex", _) $ Abs (_, _, P), n) = check (P, n + 1)
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        | check (Const ("op &", _) $ (Const ("op =", _) $ Bound m $ e) $ P, n) =
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            n > 0 andalso m = n andalso not (loose_bvar1 (P, n)) andalso
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            ((0 upto (n - 1)) subset add_loose_bnos (e, 0, []))
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        | check _ = false
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        fun tr' (_ $ abs) =
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          let val _ $ idts $ (_ $ (_ $ _ $ e) $ Q) = ex_tr' [abs]
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          in Syntax.const "@SetCompr" $ e $ idts $ Q end;
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    in if check (P, 0) then tr' P
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       else let val (x,t) = atomic_abs_tr' abs
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            in Syntax.const "@Coll" $ x $ t end
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    end;
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  in [("Collect", setcompr_tr')] end;
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*}
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subsection {* Rules and definitions *}
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text {* Isomorphisms between predicates and sets. *}
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axioms
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  mem_Collect_eq [iff]: "(a : {x. P(x)}) = P(a)"
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  Collect_mem_eq [simp]: "{x. x:A} = A"
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defs
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  Ball_def:     "Ball A P       == ALL x. x:A --> P(x)"
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  Bex_def:      "Bex A P        == EX x. x:A & P(x)"
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defs (overloaded)
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  subset_def:   "A <= B         == ALL x:A. x:B"
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  psubset_def:  "A < B          == (A::'a set) <= B & ~ A=B"
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  Compl_def:    "- A            == {x. ~x:A}"
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  set_diff_def: "A - B          == {x. x:A & ~x:B}"
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defs
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  Un_def:       "A Un B         == {x. x:A | x:B}"
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  Int_def:      "A Int B        == {x. x:A & x:B}"
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  INTER_def:    "INTER A B      == {y. ALL x:A. y: B(x)}"
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  UNION_def:    "UNION A B      == {y. EX x:A. y: B(x)}"
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  Inter_def:    "Inter S        == (INT x:S. x)"
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  Union_def:    "Union S        == (UN x:S. x)"
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  Pow_def:      "Pow A          == {B. B <= A}"
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  empty_def:    "{}             == {x. False}"
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  UNIV_def:     "UNIV           == {x. True}"
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  insert_def:   "insert a B     == {x. x=a} Un B"
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  image_def:    "f`A            == {y. EX x:A. y = f(x)}"
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subsection {* Lemmas and proof tool setup *}
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subsubsection {* Relating predicates and sets *}
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lemma CollectI: "P(a) ==> a : {x. P(x)}"
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  by simp
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lemma CollectD: "a : {x. P(x)} ==> P(a)"
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  by simp
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lemma Collect_cong: "(!!x. P x = Q x) ==> {x. P(x)} = {x. Q(x)}"
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  by simp
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lemmas CollectE = CollectD [elim_format]
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subsubsection {* Bounded quantifiers *}
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lemma ballI [intro!]: "(!!x. x:A ==> P x) ==> ALL x:A. P x"
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  by (simp add: Ball_def)
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lemmas strip = impI allI ballI
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lemma bspec [dest?]: "ALL x:A. P x ==> x:A ==> P x"
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  by (simp add: Ball_def)
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lemma ballE [elim]: "ALL x:A. P x ==> (P x ==> Q) ==> (x ~: A ==> Q) ==> Q"
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  by (unfold Ball_def) blast
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text {*
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  \medskip This tactic takes assumptions @{prop "ALL x:A. P x"} and
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  @{prop "a:A"}; creates assumption @{prop "P a"}.
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*}
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ML {*
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  local val ballE = thm "ballE"
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  in fun ball_tac i = etac ballE i THEN contr_tac (i + 1) end;
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*}
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text {*
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  Gives better instantiation for bound:
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*}
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ML_setup {*
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  claset_ref() := claset() addbefore ("bspec", datac (thm "bspec") 1);
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*}
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lemma bexI [intro]: "P x ==> x:A ==> EX x:A. P x"
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  -- {* Normally the best argument order: @{prop "P x"} constrains the
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    choice of @{prop "x:A"}. *}
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  by (unfold Bex_def) blast
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lemma rev_bexI [intro?]: "x:A ==> P x ==> EX x:A. P x"
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  -- {* The best argument order when there is only one @{prop "x:A"}. *}
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  by (unfold Bex_def) blast
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lemma bexCI: "(ALL x:A. ~P x ==> P a) ==> a:A ==> EX x:A. P x"
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  by (unfold Bex_def) blast
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lemma bexE [elim!]: "EX x:A. P x ==> (!!x. x:A ==> P x ==> Q) ==> Q"
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  by (unfold Bex_def) blast
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lemma ball_triv [simp]: "(ALL x:A. P) = ((EX x. x:A) --> P)"
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  -- {* Trival rewrite rule. *}
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  by (simp add: Ball_def)
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lemma bex_triv [simp]: "(EX x:A. P) = ((EX x. x:A) & P)"
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  -- {* Dual form for existentials. *}
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  by (simp add: Bex_def)
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lemma bex_triv_one_point1 [simp]: "(EX x:A. x = a) = (a:A)"
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  by blast
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lemma bex_triv_one_point2 [simp]: "(EX x:A. a = x) = (a:A)"
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  by blast
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lemma bex_one_point1 [simp]: "(EX x:A. x = a & P x) = (a:A & P a)"
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  by blast
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wenzelm@11979
   301
lemma bex_one_point2 [simp]: "(EX x:A. a = x & P x) = (a:A & P a)"
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   302
  by blast
wenzelm@11979
   303
wenzelm@11979
   304
lemma ball_one_point1 [simp]: "(ALL x:A. x = a --> P x) = (a:A --> P a)"
wenzelm@11979
   305
  by blast
wenzelm@11979
   306
wenzelm@11979
   307
lemma ball_one_point2 [simp]: "(ALL x:A. a = x --> P x) = (a:A --> P a)"
wenzelm@11979
   308
  by blast
wenzelm@11979
   309
wenzelm@11979
   310
ML_setup {*
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   311
  local
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   312
    val Ball_def = thm "Ball_def";
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   313
    val Bex_def = thm "Bex_def";
wenzelm@11979
   314
wenzelm@11979
   315
    val prove_bex_tac =
wenzelm@11979
   316
      rewrite_goals_tac [Bex_def] THEN Quantifier1.prove_one_point_ex_tac;
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   317
    val rearrange_bex = Quantifier1.rearrange_bex prove_bex_tac;
wenzelm@11979
   318
wenzelm@11979
   319
    val prove_ball_tac =
wenzelm@11979
   320
      rewrite_goals_tac [Ball_def] THEN Quantifier1.prove_one_point_all_tac;
wenzelm@11979
   321
    val rearrange_ball = Quantifier1.rearrange_ball prove_ball_tac;
wenzelm@11979
   322
  in
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   323
    val defBEX_regroup = Simplifier.simproc (Theory.sign_of (the_context ()))
wenzelm@13462
   324
      "defined BEX" ["EX x:A. P x & Q x"] rearrange_bex;
wenzelm@13462
   325
    val defBALL_regroup = Simplifier.simproc (Theory.sign_of (the_context ()))
wenzelm@13462
   326
      "defined BALL" ["ALL x:A. P x --> Q x"] rearrange_ball;
wenzelm@11979
   327
  end;
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   328
wenzelm@13462
   329
  Addsimprocs [defBALL_regroup, defBEX_regroup];
wenzelm@11979
   330
*}
wenzelm@11979
   331
wenzelm@11979
   332
wenzelm@11979
   333
subsubsection {* Congruence rules *}
wenzelm@11979
   334
wenzelm@11979
   335
lemma ball_cong [cong]:
wenzelm@11979
   336
  "A = B ==> (!!x. x:B ==> P x = Q x) ==>
wenzelm@11979
   337
    (ALL x:A. P x) = (ALL x:B. Q x)"
wenzelm@11979
   338
  by (simp add: Ball_def)
wenzelm@11979
   339
wenzelm@11979
   340
lemma bex_cong [cong]:
wenzelm@11979
   341
  "A = B ==> (!!x. x:B ==> P x = Q x) ==>
wenzelm@11979
   342
    (EX x:A. P x) = (EX x:B. Q x)"
wenzelm@11979
   343
  by (simp add: Bex_def cong: conj_cong)
regensbu@1273
   344
wenzelm@7238
   345
wenzelm@11979
   346
subsubsection {* Subsets *}
wenzelm@11979
   347
wenzelm@12897
   348
lemma subsetI [intro!]: "(!!x. x:A ==> x:B) ==> A \<subseteq> B"
wenzelm@11979
   349
  by (simp add: subset_def)
wenzelm@11979
   350
wenzelm@11979
   351
text {*
wenzelm@11979
   352
  \medskip Map the type @{text "'a set => anything"} to just @{typ
wenzelm@11979
   353
  'a}; for overloading constants whose first argument has type @{typ
wenzelm@11979
   354
  "'a set"}.
wenzelm@11979
   355
*}
wenzelm@11979
   356
wenzelm@12897
   357
lemma subsetD [elim]: "A \<subseteq> B ==> c \<in> A ==> c \<in> B"
wenzelm@11979
   358
  -- {* Rule in Modus Ponens style. *}
wenzelm@11979
   359
  by (unfold subset_def) blast
wenzelm@11979
   360
wenzelm@11979
   361
declare subsetD [intro?] -- FIXME
wenzelm@11979
   362
wenzelm@12897
   363
lemma rev_subsetD: "c \<in> A ==> A \<subseteq> B ==> c \<in> B"
wenzelm@11979
   364
  -- {* The same, with reversed premises for use with @{text erule} --
wenzelm@11979
   365
      cf @{text rev_mp}. *}
wenzelm@11979
   366
  by (rule subsetD)
wenzelm@11979
   367
wenzelm@11979
   368
declare rev_subsetD [intro?] -- FIXME
wenzelm@11979
   369
wenzelm@11979
   370
text {*
wenzelm@12897
   371
  \medskip Converts @{prop "A \<subseteq> B"} to @{prop "x \<in> A ==> x \<in> B"}.
wenzelm@11979
   372
*}
wenzelm@11979
   373
wenzelm@11979
   374
ML {*
wenzelm@11979
   375
  local val rev_subsetD = thm "rev_subsetD"
wenzelm@11979
   376
  in fun impOfSubs th = th RSN (2, rev_subsetD) end;
wenzelm@11979
   377
*}
wenzelm@11979
   378
wenzelm@12897
   379
lemma subsetCE [elim]: "A \<subseteq>  B ==> (c \<notin> A ==> P) ==> (c \<in> B ==> P) ==> P"
wenzelm@11979
   380
  -- {* Classical elimination rule. *}
wenzelm@11979
   381
  by (unfold subset_def) blast
wenzelm@11979
   382
wenzelm@11979
   383
text {*
wenzelm@12897
   384
  \medskip Takes assumptions @{prop "A \<subseteq> B"}; @{prop "c \<in> A"} and
wenzelm@12897
   385
  creates the assumption @{prop "c \<in> B"}.
wenzelm@11979
   386
*}
wenzelm@11979
   387
wenzelm@11979
   388
ML {*
wenzelm@11979
   389
  local val subsetCE = thm "subsetCE"
wenzelm@11979
   390
  in fun set_mp_tac i = etac subsetCE i THEN mp_tac i end;
wenzelm@11979
   391
*}
wenzelm@11979
   392
wenzelm@12897
   393
lemma contra_subsetD: "A \<subseteq> B ==> c \<notin> B ==> c \<notin> A"
wenzelm@11979
   394
  by blast
wenzelm@11979
   395
wenzelm@12897
   396
lemma subset_refl: "A \<subseteq> A"
wenzelm@11979
   397
  by fast
wenzelm@11979
   398
wenzelm@12897
   399
lemma subset_trans: "A \<subseteq> B ==> B \<subseteq> C ==> A \<subseteq> C"
wenzelm@11979
   400
  by blast
clasohm@923
   401
wenzelm@2261
   402
wenzelm@11979
   403
subsubsection {* Equality *}
wenzelm@11979
   404
paulson@13865
   405
lemma set_ext: assumes prem: "(!!x. (x:A) = (x:B))" shows "A = B"
paulson@13865
   406
  apply (rule prem [THEN ext, THEN arg_cong, THEN box_equals])
paulson@13865
   407
   apply (rule Collect_mem_eq)
paulson@13865
   408
  apply (rule Collect_mem_eq)
paulson@13865
   409
  done
paulson@13865
   410
wenzelm@12897
   411
lemma subset_antisym [intro!]: "A \<subseteq> B ==> B \<subseteq> A ==> A = B"
wenzelm@11979
   412
  -- {* Anti-symmetry of the subset relation. *}
wenzelm@12897
   413
  by (rules intro: set_ext subsetD)
wenzelm@12897
   414
wenzelm@12897
   415
lemmas equalityI [intro!] = subset_antisym
wenzelm@11979
   416
wenzelm@11979
   417
text {*
wenzelm@11979
   418
  \medskip Equality rules from ZF set theory -- are they appropriate
wenzelm@11979
   419
  here?
wenzelm@11979
   420
*}
wenzelm@11979
   421
wenzelm@12897
   422
lemma equalityD1: "A = B ==> A \<subseteq> B"
wenzelm@11979
   423
  by (simp add: subset_refl)
wenzelm@11979
   424
wenzelm@12897
   425
lemma equalityD2: "A = B ==> B \<subseteq> A"
wenzelm@11979
   426
  by (simp add: subset_refl)
wenzelm@11979
   427
wenzelm@11979
   428
text {*
wenzelm@11979
   429
  \medskip Be careful when adding this to the claset as @{text
wenzelm@11979
   430
  subset_empty} is in the simpset: @{prop "A = {}"} goes to @{prop "{}
wenzelm@12897
   431
  \<subseteq> A"} and @{prop "A \<subseteq> {}"} and then back to @{prop "A = {}"}!
wenzelm@11979
   432
*}
wenzelm@11979
   433
wenzelm@12897
   434
lemma equalityE: "A = B ==> (A \<subseteq> B ==> B \<subseteq> A ==> P) ==> P"
wenzelm@11979
   435
  by (simp add: subset_refl)
clasohm@923
   436
wenzelm@11979
   437
lemma equalityCE [elim]:
wenzelm@12897
   438
    "A = B ==> (c \<in> A ==> c \<in> B ==> P) ==> (c \<notin> A ==> c \<notin> B ==> P) ==> P"
wenzelm@11979
   439
  by blast
wenzelm@11979
   440
wenzelm@11979
   441
text {*
wenzelm@11979
   442
  \medskip Lemma for creating induction formulae -- for "pattern
wenzelm@11979
   443
  matching" on @{text p}.  To make the induction hypotheses usable,
wenzelm@11979
   444
  apply @{text spec} or @{text bspec} to put universal quantifiers over the free
wenzelm@11979
   445
  variables in @{text p}.
wenzelm@11979
   446
*}
wenzelm@11979
   447
wenzelm@11979
   448
lemma setup_induction: "p:A ==> (!!z. z:A ==> p = z --> R) ==> R"
wenzelm@11979
   449
  by simp
clasohm@923
   450
wenzelm@11979
   451
lemma eqset_imp_iff: "A = B ==> (x : A) = (x : B)"
wenzelm@11979
   452
  by simp
wenzelm@11979
   453
paulson@13865
   454
lemma eqelem_imp_iff: "x = y ==> (x : A) = (y : A)"
paulson@13865
   455
  by simp
paulson@13865
   456
wenzelm@11979
   457
wenzelm@11979
   458
subsubsection {* The universal set -- UNIV *}
wenzelm@11979
   459
wenzelm@11979
   460
lemma UNIV_I [simp]: "x : UNIV"
wenzelm@11979
   461
  by (simp add: UNIV_def)
wenzelm@11979
   462
wenzelm@11979
   463
declare UNIV_I [intro]  -- {* unsafe makes it less likely to cause problems *}
wenzelm@11979
   464
wenzelm@11979
   465
lemma UNIV_witness [intro?]: "EX x. x : UNIV"
wenzelm@11979
   466
  by simp
wenzelm@11979
   467
wenzelm@12897
   468
lemma subset_UNIV: "A \<subseteq> UNIV"
wenzelm@11979
   469
  by (rule subsetI) (rule UNIV_I)
wenzelm@2388
   470
wenzelm@11979
   471
text {*
wenzelm@11979
   472
  \medskip Eta-contracting these two rules (to remove @{text P})
wenzelm@11979
   473
  causes them to be ignored because of their interaction with
wenzelm@11979
   474
  congruence rules.
wenzelm@11979
   475
*}
wenzelm@11979
   476
wenzelm@11979
   477
lemma ball_UNIV [simp]: "Ball UNIV P = All P"
wenzelm@11979
   478
  by (simp add: Ball_def)
wenzelm@11979
   479
wenzelm@11979
   480
lemma bex_UNIV [simp]: "Bex UNIV P = Ex P"
wenzelm@11979
   481
  by (simp add: Bex_def)
wenzelm@11979
   482
wenzelm@11979
   483
wenzelm@11979
   484
subsubsection {* The empty set *}
wenzelm@11979
   485
wenzelm@11979
   486
lemma empty_iff [simp]: "(c : {}) = False"
wenzelm@11979
   487
  by (simp add: empty_def)
wenzelm@11979
   488
wenzelm@11979
   489
lemma emptyE [elim!]: "a : {} ==> P"
wenzelm@11979
   490
  by simp
wenzelm@11979
   491
wenzelm@12897
   492
lemma empty_subsetI [iff]: "{} \<subseteq> A"
wenzelm@11979
   493
    -- {* One effect is to delete the ASSUMPTION @{prop "{} <= A"} *}
wenzelm@11979
   494
  by blast
wenzelm@11979
   495
wenzelm@12897
   496
lemma equals0I: "(!!y. y \<in> A ==> False) ==> A = {}"
wenzelm@11979
   497
  by blast
wenzelm@2388
   498
wenzelm@12897
   499
lemma equals0D: "A = {} ==> a \<notin> A"
wenzelm@11979
   500
    -- {* Use for reasoning about disjointness: @{prop "A Int B = {}"} *}
wenzelm@11979
   501
  by blast
wenzelm@11979
   502
wenzelm@11979
   503
lemma ball_empty [simp]: "Ball {} P = True"
wenzelm@11979
   504
  by (simp add: Ball_def)
wenzelm@11979
   505
wenzelm@11979
   506
lemma bex_empty [simp]: "Bex {} P = False"
wenzelm@11979
   507
  by (simp add: Bex_def)
wenzelm@11979
   508
wenzelm@11979
   509
lemma UNIV_not_empty [iff]: "UNIV ~= {}"
wenzelm@11979
   510
  by (blast elim: equalityE)
wenzelm@11979
   511
wenzelm@11979
   512
wenzelm@12023
   513
subsubsection {* The Powerset operator -- Pow *}
wenzelm@11979
   514
wenzelm@12897
   515
lemma Pow_iff [iff]: "(A \<in> Pow B) = (A \<subseteq> B)"
wenzelm@11979
   516
  by (simp add: Pow_def)
wenzelm@11979
   517
wenzelm@12897
   518
lemma PowI: "A \<subseteq> B ==> A \<in> Pow B"
wenzelm@11979
   519
  by (simp add: Pow_def)
wenzelm@11979
   520
wenzelm@12897
   521
lemma PowD: "A \<in> Pow B ==> A \<subseteq> B"
wenzelm@11979
   522
  by (simp add: Pow_def)
wenzelm@11979
   523
wenzelm@12897
   524
lemma Pow_bottom: "{} \<in> Pow B"
wenzelm@11979
   525
  by simp
wenzelm@11979
   526
wenzelm@12897
   527
lemma Pow_top: "A \<in> Pow A"
wenzelm@11979
   528
  by (simp add: subset_refl)
wenzelm@2684
   529
wenzelm@2388
   530
wenzelm@11979
   531
subsubsection {* Set complement *}
wenzelm@11979
   532
wenzelm@12897
   533
lemma Compl_iff [simp]: "(c \<in> -A) = (c \<notin> A)"
wenzelm@11979
   534
  by (unfold Compl_def) blast
wenzelm@11979
   535
wenzelm@12897
   536
lemma ComplI [intro!]: "(c \<in> A ==> False) ==> c \<in> -A"
wenzelm@11979
   537
  by (unfold Compl_def) blast
wenzelm@11979
   538
wenzelm@11979
   539
text {*
wenzelm@11979
   540
  \medskip This form, with negated conclusion, works well with the
wenzelm@11979
   541
  Classical prover.  Negated assumptions behave like formulae on the
wenzelm@11979
   542
  right side of the notional turnstile ... *}
wenzelm@11979
   543
wenzelm@11979
   544
lemma ComplD: "c : -A ==> c~:A"
wenzelm@11979
   545
  by (unfold Compl_def) blast
wenzelm@11979
   546
wenzelm@11979
   547
lemmas ComplE [elim!] = ComplD [elim_format]
wenzelm@11979
   548
wenzelm@11979
   549
wenzelm@11979
   550
subsubsection {* Binary union -- Un *}
clasohm@923
   551
wenzelm@11979
   552
lemma Un_iff [simp]: "(c : A Un B) = (c:A | c:B)"
wenzelm@11979
   553
  by (unfold Un_def) blast
wenzelm@11979
   554
wenzelm@11979
   555
lemma UnI1 [elim?]: "c:A ==> c : A Un B"
wenzelm@11979
   556
  by simp
wenzelm@11979
   557
wenzelm@11979
   558
lemma UnI2 [elim?]: "c:B ==> c : A Un B"
wenzelm@11979
   559
  by simp
clasohm@923
   560
wenzelm@11979
   561
text {*
wenzelm@11979
   562
  \medskip Classical introduction rule: no commitment to @{prop A} vs
wenzelm@11979
   563
  @{prop B}.
wenzelm@11979
   564
*}
wenzelm@11979
   565
wenzelm@11979
   566
lemma UnCI [intro!]: "(c~:B ==> c:A) ==> c : A Un B"
wenzelm@11979
   567
  by auto
wenzelm@11979
   568
wenzelm@11979
   569
lemma UnE [elim!]: "c : A Un B ==> (c:A ==> P) ==> (c:B ==> P) ==> P"
wenzelm@11979
   570
  by (unfold Un_def) blast
wenzelm@11979
   571
wenzelm@11979
   572
wenzelm@12023
   573
subsubsection {* Binary intersection -- Int *}
clasohm@923
   574
wenzelm@11979
   575
lemma Int_iff [simp]: "(c : A Int B) = (c:A & c:B)"
wenzelm@11979
   576
  by (unfold Int_def) blast
wenzelm@11979
   577
wenzelm@11979
   578
lemma IntI [intro!]: "c:A ==> c:B ==> c : A Int B"
wenzelm@11979
   579
  by simp
wenzelm@11979
   580
wenzelm@11979
   581
lemma IntD1: "c : A Int B ==> c:A"
wenzelm@11979
   582
  by simp
wenzelm@11979
   583
wenzelm@11979
   584
lemma IntD2: "c : A Int B ==> c:B"
wenzelm@11979
   585
  by simp
wenzelm@11979
   586
wenzelm@11979
   587
lemma IntE [elim!]: "c : A Int B ==> (c:A ==> c:B ==> P) ==> P"
wenzelm@11979
   588
  by simp
wenzelm@11979
   589
wenzelm@11979
   590
wenzelm@12023
   591
subsubsection {* Set difference *}
wenzelm@11979
   592
wenzelm@11979
   593
lemma Diff_iff [simp]: "(c : A - B) = (c:A & c~:B)"
wenzelm@11979
   594
  by (unfold set_diff_def) blast
clasohm@923
   595
wenzelm@11979
   596
lemma DiffI [intro!]: "c : A ==> c ~: B ==> c : A - B"
wenzelm@11979
   597
  by simp
wenzelm@11979
   598
wenzelm@11979
   599
lemma DiffD1: "c : A - B ==> c : A"
wenzelm@11979
   600
  by simp
wenzelm@11979
   601
wenzelm@11979
   602
lemma DiffD2: "c : A - B ==> c : B ==> P"
wenzelm@11979
   603
  by simp
wenzelm@11979
   604
wenzelm@11979
   605
lemma DiffE [elim!]: "c : A - B ==> (c:A ==> c~:B ==> P) ==> P"
wenzelm@11979
   606
  by simp
wenzelm@11979
   607
wenzelm@11979
   608
wenzelm@11979
   609
subsubsection {* Augmenting a set -- insert *}
wenzelm@11979
   610
wenzelm@11979
   611
lemma insert_iff [simp]: "(a : insert b A) = (a = b | a:A)"
wenzelm@11979
   612
  by (unfold insert_def) blast
wenzelm@11979
   613
wenzelm@11979
   614
lemma insertI1: "a : insert a B"
wenzelm@11979
   615
  by simp
wenzelm@11979
   616
wenzelm@11979
   617
lemma insertI2: "a : B ==> a : insert b B"
wenzelm@11979
   618
  by simp
clasohm@923
   619
wenzelm@11979
   620
lemma insertE [elim!]: "a : insert b A ==> (a = b ==> P) ==> (a:A ==> P) ==> P"
wenzelm@11979
   621
  by (unfold insert_def) blast
wenzelm@11979
   622
wenzelm@11979
   623
lemma insertCI [intro!]: "(a~:B ==> a = b) ==> a: insert b B"
wenzelm@11979
   624
  -- {* Classical introduction rule. *}
wenzelm@11979
   625
  by auto
wenzelm@11979
   626
wenzelm@12897
   627
lemma subset_insert_iff: "(A \<subseteq> insert x B) = (if x:A then A - {x} \<subseteq> B else A \<subseteq> B)"
wenzelm@11979
   628
  by auto
wenzelm@11979
   629
wenzelm@11979
   630
wenzelm@11979
   631
subsubsection {* Singletons, using insert *}
wenzelm@11979
   632
wenzelm@11979
   633
lemma singletonI [intro!]: "a : {a}"
wenzelm@11979
   634
    -- {* Redundant? But unlike @{text insertCI}, it proves the subgoal immediately! *}
wenzelm@11979
   635
  by (rule insertI1)
wenzelm@11979
   636
wenzelm@11979
   637
lemma singletonD: "b : {a} ==> b = a"
wenzelm@11979
   638
  by blast
wenzelm@11979
   639
wenzelm@11979
   640
lemmas singletonE [elim!] = singletonD [elim_format]
wenzelm@11979
   641
wenzelm@11979
   642
lemma singleton_iff: "(b : {a}) = (b = a)"
wenzelm@11979
   643
  by blast
wenzelm@11979
   644
wenzelm@11979
   645
lemma singleton_inject [dest!]: "{a} = {b} ==> a = b"
wenzelm@11979
   646
  by blast
wenzelm@11979
   647
wenzelm@12897
   648
lemma singleton_insert_inj_eq [iff]: "({b} = insert a A) = (a = b & A \<subseteq> {b})"
wenzelm@11979
   649
  by blast
wenzelm@11979
   650
wenzelm@12897
   651
lemma singleton_insert_inj_eq' [iff]: "(insert a A = {b}) = (a = b & A \<subseteq> {b})"
wenzelm@11979
   652
  by blast
wenzelm@11979
   653
wenzelm@12897
   654
lemma subset_singletonD: "A \<subseteq> {x} ==> A = {} | A = {x}"
wenzelm@11979
   655
  by fast
wenzelm@11979
   656
wenzelm@11979
   657
lemma singleton_conv [simp]: "{x. x = a} = {a}"
wenzelm@11979
   658
  by blast
wenzelm@11979
   659
wenzelm@11979
   660
lemma singleton_conv2 [simp]: "{x. a = x} = {a}"
wenzelm@11979
   661
  by blast
clasohm@923
   662
wenzelm@12897
   663
lemma diff_single_insert: "A - {x} \<subseteq> B ==> x \<in> A ==> A \<subseteq> insert x B"
wenzelm@11979
   664
  by blast
wenzelm@11979
   665
wenzelm@11979
   666
wenzelm@11979
   667
subsubsection {* Unions of families *}
wenzelm@11979
   668
wenzelm@11979
   669
text {*
wenzelm@11979
   670
  @{term [source] "UN x:A. B x"} is @{term "Union (B`A)"}.
wenzelm@11979
   671
*}
wenzelm@11979
   672
wenzelm@11979
   673
lemma UN_iff [simp]: "(b: (UN x:A. B x)) = (EX x:A. b: B x)"
wenzelm@11979
   674
  by (unfold UNION_def) blast
wenzelm@11979
   675
wenzelm@11979
   676
lemma UN_I [intro]: "a:A ==> b: B a ==> b: (UN x:A. B x)"
wenzelm@11979
   677
  -- {* The order of the premises presupposes that @{term A} is rigid;
wenzelm@11979
   678
    @{term b} may be flexible. *}
wenzelm@11979
   679
  by auto
wenzelm@11979
   680
wenzelm@11979
   681
lemma UN_E [elim!]: "b : (UN x:A. B x) ==> (!!x. x:A ==> b: B x ==> R) ==> R"
wenzelm@11979
   682
  by (unfold UNION_def) blast
clasohm@923
   683
wenzelm@11979
   684
lemma UN_cong [cong]:
wenzelm@11979
   685
    "A = B ==> (!!x. x:B ==> C x = D x) ==> (UN x:A. C x) = (UN x:B. D x)"
wenzelm@11979
   686
  by (simp add: UNION_def)
wenzelm@11979
   687
wenzelm@11979
   688
wenzelm@11979
   689
subsubsection {* Intersections of families *}
wenzelm@11979
   690
wenzelm@11979
   691
text {* @{term [source] "INT x:A. B x"} is @{term "Inter (B`A)"}. *}
wenzelm@11979
   692
wenzelm@11979
   693
lemma INT_iff [simp]: "(b: (INT x:A. B x)) = (ALL x:A. b: B x)"
wenzelm@11979
   694
  by (unfold INTER_def) blast
clasohm@923
   695
wenzelm@11979
   696
lemma INT_I [intro!]: "(!!x. x:A ==> b: B x) ==> b : (INT x:A. B x)"
wenzelm@11979
   697
  by (unfold INTER_def) blast
wenzelm@11979
   698
wenzelm@11979
   699
lemma INT_D [elim]: "b : (INT x:A. B x) ==> a:A ==> b: B a"
wenzelm@11979
   700
  by auto
wenzelm@11979
   701
wenzelm@11979
   702
lemma INT_E [elim]: "b : (INT x:A. B x) ==> (b: B a ==> R) ==> (a~:A ==> R) ==> R"
wenzelm@11979
   703
  -- {* "Classical" elimination -- by the Excluded Middle on @{prop "a:A"}. *}
wenzelm@11979
   704
  by (unfold INTER_def) blast
wenzelm@11979
   705
wenzelm@11979
   706
lemma INT_cong [cong]:
wenzelm@11979
   707
    "A = B ==> (!!x. x:B ==> C x = D x) ==> (INT x:A. C x) = (INT x:B. D x)"
wenzelm@11979
   708
  by (simp add: INTER_def)
wenzelm@7238
   709
clasohm@923
   710
wenzelm@11979
   711
subsubsection {* Union *}
wenzelm@11979
   712
wenzelm@11979
   713
lemma Union_iff [simp]: "(A : Union C) = (EX X:C. A:X)"
wenzelm@11979
   714
  by (unfold Union_def) blast
wenzelm@11979
   715
wenzelm@11979
   716
lemma UnionI [intro]: "X:C ==> A:X ==> A : Union C"
wenzelm@11979
   717
  -- {* The order of the premises presupposes that @{term C} is rigid;
wenzelm@11979
   718
    @{term A} may be flexible. *}
wenzelm@11979
   719
  by auto
wenzelm@11979
   720
wenzelm@11979
   721
lemma UnionE [elim!]: "A : Union C ==> (!!X. A:X ==> X:C ==> R) ==> R"
wenzelm@11979
   722
  by (unfold Union_def) blast
wenzelm@11979
   723
wenzelm@11979
   724
wenzelm@11979
   725
subsubsection {* Inter *}
wenzelm@11979
   726
wenzelm@11979
   727
lemma Inter_iff [simp]: "(A : Inter C) = (ALL X:C. A:X)"
wenzelm@11979
   728
  by (unfold Inter_def) blast
wenzelm@11979
   729
wenzelm@11979
   730
lemma InterI [intro!]: "(!!X. X:C ==> A:X) ==> A : Inter C"
wenzelm@11979
   731
  by (simp add: Inter_def)
wenzelm@11979
   732
wenzelm@11979
   733
text {*
wenzelm@11979
   734
  \medskip A ``destruct'' rule -- every @{term X} in @{term C}
wenzelm@11979
   735
  contains @{term A} as an element, but @{prop "A:X"} can hold when
wenzelm@11979
   736
  @{prop "X:C"} does not!  This rule is analogous to @{text spec}.
wenzelm@11979
   737
*}
wenzelm@11979
   738
wenzelm@11979
   739
lemma InterD [elim]: "A : Inter C ==> X:C ==> A:X"
wenzelm@11979
   740
  by auto
wenzelm@11979
   741
wenzelm@11979
   742
lemma InterE [elim]: "A : Inter C ==> (X~:C ==> R) ==> (A:X ==> R) ==> R"
wenzelm@11979
   743
  -- {* ``Classical'' elimination rule -- does not require proving
wenzelm@11979
   744
    @{prop "X:C"}. *}
wenzelm@11979
   745
  by (unfold Inter_def) blast
wenzelm@11979
   746
wenzelm@11979
   747
text {*
wenzelm@11979
   748
  \medskip Image of a set under a function.  Frequently @{term b} does
wenzelm@11979
   749
  not have the syntactic form of @{term "f x"}.
wenzelm@11979
   750
*}
wenzelm@11979
   751
wenzelm@11979
   752
lemma image_eqI [simp, intro]: "b = f x ==> x:A ==> b : f`A"
wenzelm@11979
   753
  by (unfold image_def) blast
wenzelm@11979
   754
wenzelm@11979
   755
lemma imageI: "x : A ==> f x : f ` A"
wenzelm@11979
   756
  by (rule image_eqI) (rule refl)
wenzelm@11979
   757
wenzelm@11979
   758
lemma rev_image_eqI: "x:A ==> b = f x ==> b : f`A"
wenzelm@11979
   759
  -- {* This version's more effective when we already have the
wenzelm@11979
   760
    required @{term x}. *}
wenzelm@11979
   761
  by (unfold image_def) blast
wenzelm@11979
   762
wenzelm@11979
   763
lemma imageE [elim!]:
wenzelm@11979
   764
  "b : (%x. f x)`A ==> (!!x. b = f x ==> x:A ==> P) ==> P"
wenzelm@11979
   765
  -- {* The eta-expansion gives variable-name preservation. *}
wenzelm@11979
   766
  by (unfold image_def) blast
wenzelm@11979
   767
wenzelm@11979
   768
lemma image_Un: "f`(A Un B) = f`A Un f`B"
wenzelm@11979
   769
  by blast
wenzelm@11979
   770
wenzelm@11979
   771
lemma image_iff: "(z : f`A) = (EX x:A. z = f x)"
wenzelm@11979
   772
  by blast
wenzelm@11979
   773
wenzelm@12897
   774
lemma image_subset_iff: "(f`A \<subseteq> B) = (\<forall>x\<in>A. f x \<in> B)"
wenzelm@11979
   775
  -- {* This rewrite rule would confuse users if made default. *}
wenzelm@11979
   776
  by blast
wenzelm@11979
   777
wenzelm@12897
   778
lemma subset_image_iff: "(B \<subseteq> f`A) = (EX AA. AA \<subseteq> A & B = f`AA)"
wenzelm@11979
   779
  apply safe
wenzelm@11979
   780
   prefer 2 apply fast
wenzelm@11979
   781
  apply (rule_tac x = "{a. a : A & f a : B}" in exI)
wenzelm@11979
   782
  apply fast
wenzelm@11979
   783
  done
wenzelm@11979
   784
wenzelm@12897
   785
lemma image_subsetI: "(!!x. x \<in> A ==> f x \<in> B) ==> f`A \<subseteq> B"
wenzelm@11979
   786
  -- {* Replaces the three steps @{text subsetI}, @{text imageE},
wenzelm@11979
   787
    @{text hypsubst}, but breaks too many existing proofs. *}
wenzelm@11979
   788
  by blast
wenzelm@11979
   789
wenzelm@11979
   790
text {*
wenzelm@11979
   791
  \medskip Range of a function -- just a translation for image!
wenzelm@11979
   792
*}
wenzelm@11979
   793
wenzelm@12897
   794
lemma range_eqI: "b = f x ==> b \<in> range f"
wenzelm@11979
   795
  by simp
wenzelm@11979
   796
wenzelm@12897
   797
lemma rangeI: "f x \<in> range f"
wenzelm@11979
   798
  by simp
wenzelm@11979
   799
wenzelm@12897
   800
lemma rangeE [elim?]: "b \<in> range (\<lambda>x. f x) ==> (!!x. b = f x ==> P) ==> P"
wenzelm@11979
   801
  by blast
wenzelm@11979
   802
wenzelm@11979
   803
wenzelm@11979
   804
subsubsection {* Set reasoning tools *}
wenzelm@11979
   805
wenzelm@11979
   806
text {*
wenzelm@11979
   807
  Rewrite rules for boolean case-splitting: faster than @{text
wenzelm@11979
   808
  "split_if [split]"}.
wenzelm@11979
   809
*}
wenzelm@11979
   810
wenzelm@11979
   811
lemma split_if_eq1: "((if Q then x else y) = b) = ((Q --> x = b) & (~ Q --> y = b))"
wenzelm@11979
   812
  by (rule split_if)
wenzelm@11979
   813
wenzelm@11979
   814
lemma split_if_eq2: "(a = (if Q then x else y)) = ((Q --> a = x) & (~ Q --> a = y))"
wenzelm@11979
   815
  by (rule split_if)
wenzelm@11979
   816
wenzelm@11979
   817
text {*
wenzelm@11979
   818
  Split ifs on either side of the membership relation.  Not for @{text
wenzelm@11979
   819
  "[simp]"} -- can cause goals to blow up!
wenzelm@11979
   820
*}
wenzelm@11979
   821
wenzelm@11979
   822
lemma split_if_mem1: "((if Q then x else y) : b) = ((Q --> x : b) & (~ Q --> y : b))"
wenzelm@11979
   823
  by (rule split_if)
wenzelm@11979
   824
wenzelm@11979
   825
lemma split_if_mem2: "(a : (if Q then x else y)) = ((Q --> a : x) & (~ Q --> a : y))"
wenzelm@11979
   826
  by (rule split_if)
wenzelm@11979
   827
wenzelm@11979
   828
lemmas split_ifs = if_bool_eq_conj split_if_eq1 split_if_eq2 split_if_mem1 split_if_mem2
wenzelm@11979
   829
wenzelm@11979
   830
lemmas mem_simps =
wenzelm@11979
   831
  insert_iff empty_iff Un_iff Int_iff Compl_iff Diff_iff
wenzelm@11979
   832
  mem_Collect_eq UN_iff Union_iff INT_iff Inter_iff
wenzelm@11979
   833
  -- {* Each of these has ALREADY been added @{text "[simp]"} above. *}
wenzelm@11979
   834
wenzelm@11979
   835
(*Would like to add these, but the existing code only searches for the
wenzelm@11979
   836
  outer-level constant, which in this case is just "op :"; we instead need
wenzelm@11979
   837
  to use term-nets to associate patterns with rules.  Also, if a rule fails to
wenzelm@11979
   838
  apply, then the formula should be kept.
wenzelm@11979
   839
  [("uminus", Compl_iff RS iffD1), ("op -", [Diff_iff RS iffD1]),
wenzelm@11979
   840
   ("op Int", [IntD1,IntD2]),
wenzelm@11979
   841
   ("Collect", [CollectD]), ("Inter", [InterD]), ("INTER", [INT_D])]
wenzelm@11979
   842
 *)
wenzelm@11979
   843
wenzelm@11979
   844
ML_setup {*
wenzelm@11979
   845
  val mksimps_pairs = [("Ball", [thm "bspec"])] @ mksimps_pairs;
wenzelm@11979
   846
  simpset_ref() := simpset() setmksimps (mksimps mksimps_pairs);
wenzelm@11979
   847
*}
wenzelm@11979
   848
wenzelm@11979
   849
declare subset_UNIV [simp] subset_refl [simp]
wenzelm@11979
   850
wenzelm@11979
   851
wenzelm@11979
   852
subsubsection {* The ``proper subset'' relation *}
wenzelm@11979
   853
wenzelm@12897
   854
lemma psubsetI [intro!]: "A \<subseteq> B ==> A \<noteq> B ==> A \<subset> B"
wenzelm@11979
   855
  by (unfold psubset_def) blast
wenzelm@11979
   856
paulson@13624
   857
lemma psubsetE [elim!]: 
paulson@13624
   858
    "[|A \<subset> B;  [|A \<subseteq> B; ~ (B\<subseteq>A)|] ==> R|] ==> R"
paulson@13624
   859
  by (unfold psubset_def) blast
paulson@13624
   860
wenzelm@11979
   861
lemma psubset_insert_iff:
wenzelm@12897
   862
  "(A \<subset> insert x B) = (if x \<in> B then A \<subset> B else if x \<in> A then A - {x} \<subset> B else A \<subseteq> B)"
wenzelm@12897
   863
  by (auto simp add: psubset_def subset_insert_iff)
wenzelm@12897
   864
wenzelm@12897
   865
lemma psubset_eq: "(A \<subset> B) = (A \<subseteq> B & A \<noteq> B)"
wenzelm@11979
   866
  by (simp only: psubset_def)
wenzelm@11979
   867
wenzelm@12897
   868
lemma psubset_imp_subset: "A \<subset> B ==> A \<subseteq> B"
wenzelm@11979
   869
  by (simp add: psubset_eq)
wenzelm@11979
   870
wenzelm@12897
   871
lemma psubset_subset_trans: "A \<subset> B ==> B \<subseteq> C ==> A \<subset> C"
wenzelm@11979
   872
  by (auto simp add: psubset_eq)
wenzelm@11979
   873
wenzelm@12897
   874
lemma subset_psubset_trans: "A \<subseteq> B ==> B \<subset> C ==> A \<subset> C"
wenzelm@11979
   875
  by (auto simp add: psubset_eq)
wenzelm@11979
   876
wenzelm@12897
   877
lemma psubset_imp_ex_mem: "A \<subset> B ==> \<exists>b. b \<in> (B - A)"
wenzelm@11979
   878
  by (unfold psubset_def) blast
wenzelm@11979
   879
wenzelm@11979
   880
lemma atomize_ball:
wenzelm@12897
   881
    "(!!x. x \<in> A ==> P x) == Trueprop (\<forall>x\<in>A. P x)"
wenzelm@11979
   882
  by (simp only: Ball_def atomize_all atomize_imp)
wenzelm@11979
   883
wenzelm@11979
   884
declare atomize_ball [symmetric, rulify]
wenzelm@11979
   885
wenzelm@11979
   886
wenzelm@11979
   887
subsection {* Further set-theory lemmas *}
wenzelm@11979
   888
wenzelm@12897
   889
subsubsection {* Derived rules involving subsets. *}
wenzelm@12897
   890
wenzelm@12897
   891
text {* @{text insert}. *}
wenzelm@12897
   892
wenzelm@12897
   893
lemma subset_insertI: "B \<subseteq> insert a B"
wenzelm@12897
   894
  apply (rule subsetI)
wenzelm@12897
   895
  apply (erule insertI2)
wenzelm@12897
   896
  done
wenzelm@12897
   897
wenzelm@12897
   898
lemma subset_insert: "x \<notin> A ==> (A \<subseteq> insert x B) = (A \<subseteq> B)"
wenzelm@12897
   899
  by blast
wenzelm@12897
   900
wenzelm@12897
   901
wenzelm@12897
   902
text {* \medskip Big Union -- least upper bound of a set. *}
wenzelm@12897
   903
wenzelm@12897
   904
lemma Union_upper: "B \<in> A ==> B \<subseteq> Union A"
wenzelm@12897
   905
  by (rules intro: subsetI UnionI)
wenzelm@12897
   906
wenzelm@12897
   907
lemma Union_least: "(!!X. X \<in> A ==> X \<subseteq> C) ==> Union A \<subseteq> C"
wenzelm@12897
   908
  by (rules intro: subsetI elim: UnionE dest: subsetD)
wenzelm@12897
   909
wenzelm@12897
   910
wenzelm@12897
   911
text {* \medskip General union. *}
wenzelm@12897
   912
wenzelm@12897
   913
lemma UN_upper: "a \<in> A ==> B a \<subseteq> (\<Union>x\<in>A. B x)"
wenzelm@12897
   914
  by blast
wenzelm@12897
   915
wenzelm@12897
   916
lemma UN_least: "(!!x. x \<in> A ==> B x \<subseteq> C) ==> (\<Union>x\<in>A. B x) \<subseteq> C"
wenzelm@12897
   917
  by (rules intro: subsetI elim: UN_E dest: subsetD)
wenzelm@12897
   918
wenzelm@12897
   919
wenzelm@12897
   920
text {* \medskip Big Intersection -- greatest lower bound of a set. *}
wenzelm@12897
   921
wenzelm@12897
   922
lemma Inter_lower: "B \<in> A ==> Inter A \<subseteq> B"
wenzelm@12897
   923
  by blast
wenzelm@12897
   924
wenzelm@12897
   925
lemma Inter_greatest: "(!!X. X \<in> A ==> C \<subseteq> X) ==> C \<subseteq> Inter A"
wenzelm@12897
   926
  by (rules intro: InterI subsetI dest: subsetD)
wenzelm@12897
   927
wenzelm@12897
   928
lemma INT_lower: "a \<in> A ==> (\<Inter>x\<in>A. B x) \<subseteq> B a"
wenzelm@12897
   929
  by blast
wenzelm@12897
   930
wenzelm@12897
   931
lemma INT_greatest: "(!!x. x \<in> A ==> C \<subseteq> B x) ==> C \<subseteq> (\<Inter>x\<in>A. B x)"
wenzelm@12897
   932
  by (rules intro: INT_I subsetI dest: subsetD)
wenzelm@12897
   933
wenzelm@12897
   934
wenzelm@12897
   935
text {* \medskip Finite Union -- the least upper bound of two sets. *}
wenzelm@12897
   936
wenzelm@12897
   937
lemma Un_upper1: "A \<subseteq> A \<union> B"
wenzelm@12897
   938
  by blast
wenzelm@12897
   939
wenzelm@12897
   940
lemma Un_upper2: "B \<subseteq> A \<union> B"
wenzelm@12897
   941
  by blast
wenzelm@12897
   942
wenzelm@12897
   943
lemma Un_least: "A \<subseteq> C ==> B \<subseteq> C ==> A \<union> B \<subseteq> C"
wenzelm@12897
   944
  by blast
wenzelm@12897
   945
wenzelm@12897
   946
wenzelm@12897
   947
text {* \medskip Finite Intersection -- the greatest lower bound of two sets. *}
wenzelm@12897
   948
wenzelm@12897
   949
lemma Int_lower1: "A \<inter> B \<subseteq> A"
wenzelm@12897
   950
  by blast
wenzelm@12897
   951
wenzelm@12897
   952
lemma Int_lower2: "A \<inter> B \<subseteq> B"
wenzelm@12897
   953
  by blast
wenzelm@12897
   954
wenzelm@12897
   955
lemma Int_greatest: "C \<subseteq> A ==> C \<subseteq> B ==> C \<subseteq> A \<inter> B"
wenzelm@12897
   956
  by blast
wenzelm@12897
   957
wenzelm@12897
   958
wenzelm@12897
   959
text {* \medskip Set difference. *}
wenzelm@12897
   960
wenzelm@12897
   961
lemma Diff_subset: "A - B \<subseteq> A"
wenzelm@12897
   962
  by blast
wenzelm@12897
   963
wenzelm@12897
   964
wenzelm@12897
   965
text {* \medskip Monotonicity. *}
wenzelm@12897
   966
wenzelm@13421
   967
lemma mono_Un: includes mono shows "f A \<union> f B \<subseteq> f (A \<union> B)"
wenzelm@12897
   968
  apply (rule Un_least)
wenzelm@13421
   969
   apply (rule Un_upper1 [THEN mono])
wenzelm@13421
   970
  apply (rule Un_upper2 [THEN mono])
wenzelm@12897
   971
  done
wenzelm@12897
   972
wenzelm@13421
   973
lemma mono_Int: includes mono shows "f (A \<inter> B) \<subseteq> f A \<inter> f B"
wenzelm@12897
   974
  apply (rule Int_greatest)
wenzelm@13421
   975
   apply (rule Int_lower1 [THEN mono])
wenzelm@13421
   976
  apply (rule Int_lower2 [THEN mono])
wenzelm@12897
   977
  done
wenzelm@12897
   978
wenzelm@12897
   979
wenzelm@12897
   980
subsubsection {* Equalities involving union, intersection, inclusion, etc. *}
wenzelm@12897
   981
wenzelm@12897
   982
text {* @{text "{}"}. *}
wenzelm@12897
   983
wenzelm@12897
   984
lemma Collect_const [simp]: "{s. P} = (if P then UNIV else {})"
wenzelm@12897
   985
  -- {* supersedes @{text "Collect_False_empty"} *}
wenzelm@12897
   986
  by auto
wenzelm@12897
   987
wenzelm@12897
   988
lemma subset_empty [simp]: "(A \<subseteq> {}) = (A = {})"
wenzelm@12897
   989
  by blast
wenzelm@12897
   990
wenzelm@12897
   991
lemma not_psubset_empty [iff]: "\<not> (A < {})"
wenzelm@12897
   992
  by (unfold psubset_def) blast
wenzelm@12897
   993
wenzelm@12897
   994
lemma Collect_empty_eq [simp]: "(Collect P = {}) = (\<forall>x. \<not> P x)"
wenzelm@12897
   995
  by auto
wenzelm@12897
   996
wenzelm@12897
   997
lemma Collect_neg_eq: "{x. \<not> P x} = - {x. P x}"
wenzelm@12897
   998
  by blast
wenzelm@12897
   999
wenzelm@12897
  1000
lemma Collect_disj_eq: "{x. P x | Q x} = {x. P x} \<union> {x. Q x}"
wenzelm@12897
  1001
  by blast
wenzelm@12897
  1002
wenzelm@12897
  1003
lemma Collect_conj_eq: "{x. P x & Q x} = {x. P x} \<inter> {x. Q x}"
wenzelm@12897
  1004
  by blast
wenzelm@12897
  1005
wenzelm@12897
  1006
lemma Collect_all_eq: "{x. \<forall>y. P x y} = (\<Inter>y. {x. P x y})"
wenzelm@12897
  1007
  by blast
wenzelm@12897
  1008
wenzelm@12897
  1009
lemma Collect_ball_eq: "{x. \<forall>y\<in>A. P x y} = (\<Inter>y\<in>A. {x. P x y})"
wenzelm@12897
  1010
  by blast
wenzelm@12897
  1011
wenzelm@12897
  1012
lemma Collect_ex_eq: "{x. \<exists>y. P x y} = (\<Union>y. {x. P x y})"
wenzelm@12897
  1013
  by blast
wenzelm@12897
  1014
wenzelm@12897
  1015
lemma Collect_bex_eq: "{x. \<exists>y\<in>A. P x y} = (\<Union>y\<in>A. {x. P x y})"
wenzelm@12897
  1016
  by blast
wenzelm@12897
  1017
wenzelm@12897
  1018
wenzelm@12897
  1019
text {* \medskip @{text insert}. *}
wenzelm@12897
  1020
wenzelm@12897
  1021
lemma insert_is_Un: "insert a A = {a} Un A"
wenzelm@12897
  1022
  -- {* NOT SUITABLE FOR REWRITING since @{text "{a} == insert a {}"} *}
wenzelm@12897
  1023
  by blast
wenzelm@12897
  1024
wenzelm@12897
  1025
lemma insert_not_empty [simp]: "insert a A \<noteq> {}"
wenzelm@12897
  1026
  by blast
wenzelm@12897
  1027
wenzelm@12897
  1028
lemmas empty_not_insert [simp] = insert_not_empty [symmetric, standard]
wenzelm@12897
  1029
wenzelm@12897
  1030
lemma insert_absorb: "a \<in> A ==> insert a A = A"
wenzelm@12897
  1031
  -- {* @{text "[simp]"} causes recursive calls when there are nested inserts *}
wenzelm@12897
  1032
  -- {* with \emph{quadratic} running time *}
wenzelm@12897
  1033
  by blast
wenzelm@12897
  1034
wenzelm@12897
  1035
lemma insert_absorb2 [simp]: "insert x (insert x A) = insert x A"
wenzelm@12897
  1036
  by blast
wenzelm@12897
  1037
wenzelm@12897
  1038
lemma insert_commute: "insert x (insert y A) = insert y (insert x A)"
wenzelm@12897
  1039
  by blast
wenzelm@12897
  1040
wenzelm@12897
  1041
lemma insert_subset [simp]: "(insert x A \<subseteq> B) = (x \<in> B & A \<subseteq> B)"
wenzelm@12897
  1042
  by blast
wenzelm@12897
  1043
wenzelm@12897
  1044
lemma mk_disjoint_insert: "a \<in> A ==> \<exists>B. A = insert a B & a \<notin> B"
wenzelm@12897
  1045
  -- {* use new @{text B} rather than @{text "A - {a}"} to avoid infinite unfolding *}
wenzelm@12897
  1046
  apply (rule_tac x = "A - {a}" in exI)
wenzelm@12897
  1047
  apply blast
wenzelm@12897
  1048
  done
wenzelm@12897
  1049
wenzelm@12897
  1050
lemma insert_Collect: "insert a (Collect P) = {u. u \<noteq> a --> P u}"
wenzelm@12897
  1051
  by auto
wenzelm@12897
  1052
wenzelm@12897
  1053
lemma UN_insert_distrib: "u \<in> A ==> (\<Union>x\<in>A. insert a (B x)) = insert a (\<Union>x\<in>A. B x)"
wenzelm@12897
  1054
  by blast
wenzelm@12897
  1055
nipkow@13103
  1056
lemma insert_disjoint[simp]:
nipkow@13103
  1057
 "(insert a A \<inter> B = {}) = (a \<notin> B \<and> A \<inter> B = {})"
nipkow@13103
  1058
by blast
nipkow@13103
  1059
nipkow@13103
  1060
lemma disjoint_insert[simp]:
nipkow@13103
  1061
 "(B \<inter> insert a A = {}) = (a \<notin> B \<and> B \<inter> A = {})"
nipkow@13103
  1062
by blast
wenzelm@12897
  1063
wenzelm@12897
  1064
text {* \medskip @{text image}. *}
wenzelm@12897
  1065
wenzelm@12897
  1066
lemma image_empty [simp]: "f`{} = {}"
wenzelm@12897
  1067
  by blast
wenzelm@12897
  1068
wenzelm@12897
  1069
lemma image_insert [simp]: "f ` insert a B = insert (f a) (f`B)"
wenzelm@12897
  1070
  by blast
wenzelm@12897
  1071
wenzelm@12897
  1072
lemma image_constant: "x \<in> A ==> (\<lambda>x. c) ` A = {c}"
wenzelm@12897
  1073
  by blast
wenzelm@12897
  1074
wenzelm@12897
  1075
lemma image_image: "f ` (g ` A) = (\<lambda>x. f (g x)) ` A"
wenzelm@12897
  1076
  by blast
wenzelm@12897
  1077
wenzelm@12897
  1078
lemma insert_image [simp]: "x \<in> A ==> insert (f x) (f`A) = f`A"
wenzelm@12897
  1079
  by blast
wenzelm@12897
  1080
wenzelm@12897
  1081
lemma image_is_empty [iff]: "(f`A = {}) = (A = {})"
wenzelm@12897
  1082
  by blast
wenzelm@12897
  1083
wenzelm@12897
  1084
lemma image_Collect: "f ` {x. P x} = {f x | x. P x}"
wenzelm@12897
  1085
  -- {* NOT suitable as a default simprule: the RHS isn't simpler than the LHS, *}
wenzelm@12897
  1086
  -- {* with its implicit quantifier and conjunction.  Also image enjoys better *}
wenzelm@12897
  1087
  -- {* equational properties than does the RHS. *}
wenzelm@12897
  1088
  by blast
wenzelm@12897
  1089
wenzelm@12897
  1090
lemma if_image_distrib [simp]:
wenzelm@12897
  1091
  "(\<lambda>x. if P x then f x else g x) ` S
wenzelm@12897
  1092
    = (f ` (S \<inter> {x. P x})) \<union> (g ` (S \<inter> {x. \<not> P x}))"
wenzelm@12897
  1093
  by (auto simp add: image_def)
wenzelm@12897
  1094
wenzelm@12897
  1095
lemma image_cong: "M = N ==> (!!x. x \<in> N ==> f x = g x) ==> f`M = g`N"
wenzelm@12897
  1096
  by (simp add: image_def)
wenzelm@12897
  1097
wenzelm@12897
  1098
wenzelm@12897
  1099
text {* \medskip @{text range}. *}
wenzelm@12897
  1100
wenzelm@12897
  1101
lemma full_SetCompr_eq: "{u. \<exists>x. u = f x} = range f"
wenzelm@12897
  1102
  by auto
wenzelm@12897
  1103
wenzelm@12897
  1104
lemma range_composition [simp]: "range (\<lambda>x. f (g x)) = f`range g"
wenzelm@12897
  1105
  apply (subst image_image)
wenzelm@12897
  1106
  apply simp
wenzelm@12897
  1107
  done
wenzelm@12897
  1108
wenzelm@12897
  1109
wenzelm@12897
  1110
text {* \medskip @{text Int} *}
wenzelm@12897
  1111
wenzelm@12897
  1112
lemma Int_absorb [simp]: "A \<inter> A = A"
wenzelm@12897
  1113
  by blast
wenzelm@12897
  1114
wenzelm@12897
  1115
lemma Int_left_absorb: "A \<inter> (A \<inter> B) = A \<inter> B"
wenzelm@12897
  1116
  by blast
wenzelm@12897
  1117
wenzelm@12897
  1118
lemma Int_commute: "A \<inter> B = B \<inter> A"
wenzelm@12897
  1119
  by blast
wenzelm@12897
  1120
wenzelm@12897
  1121
lemma Int_left_commute: "A \<inter> (B \<inter> C) = B \<inter> (A \<inter> C)"
wenzelm@12897
  1122
  by blast
wenzelm@12897
  1123
wenzelm@12897
  1124
lemma Int_assoc: "(A \<inter> B) \<inter> C = A \<inter> (B \<inter> C)"
wenzelm@12897
  1125
  by blast
wenzelm@12897
  1126
wenzelm@12897
  1127
lemmas Int_ac = Int_assoc Int_left_absorb Int_commute Int_left_commute
wenzelm@12897
  1128
  -- {* Intersection is an AC-operator *}
wenzelm@12897
  1129
wenzelm@12897
  1130
lemma Int_absorb1: "B \<subseteq> A ==> A \<inter> B = B"
wenzelm@12897
  1131
  by blast
wenzelm@12897
  1132
wenzelm@12897
  1133
lemma Int_absorb2: "A \<subseteq> B ==> A \<inter> B = A"
wenzelm@12897
  1134
  by blast
wenzelm@12897
  1135
wenzelm@12897
  1136
lemma Int_empty_left [simp]: "{} \<inter> B = {}"
wenzelm@12897
  1137
  by blast
wenzelm@12897
  1138
wenzelm@12897
  1139
lemma Int_empty_right [simp]: "A \<inter> {} = {}"
wenzelm@12897
  1140
  by blast
wenzelm@12897
  1141
wenzelm@12897
  1142
lemma disjoint_eq_subset_Compl: "(A \<inter> B = {}) = (A \<subseteq> -B)"
wenzelm@12897
  1143
  by blast
wenzelm@12897
  1144
wenzelm@12897
  1145
lemma disjoint_iff_not_equal: "(A \<inter> B = {}) = (\<forall>x\<in>A. \<forall>y\<in>B. x \<noteq> y)"
wenzelm@12897
  1146
  by blast
wenzelm@12897
  1147
wenzelm@12897
  1148
lemma Int_UNIV_left [simp]: "UNIV \<inter> B = B"
wenzelm@12897
  1149
  by blast
wenzelm@12897
  1150
wenzelm@12897
  1151
lemma Int_UNIV_right [simp]: "A \<inter> UNIV = A"
wenzelm@12897
  1152
  by blast
wenzelm@12897
  1153
wenzelm@12897
  1154
lemma Int_eq_Inter: "A \<inter> B = \<Inter>{A, B}"
wenzelm@12897
  1155
  by blast
wenzelm@12897
  1156
wenzelm@12897
  1157
lemma Int_Un_distrib: "A \<inter> (B \<union> C) = (A \<inter> B) \<union> (A \<inter> C)"
wenzelm@12897
  1158
  by blast
wenzelm@12897
  1159
wenzelm@12897
  1160
lemma Int_Un_distrib2: "(B \<union> C) \<inter> A = (B \<inter> A) \<union> (C \<inter> A)"
wenzelm@12897
  1161
  by blast
wenzelm@12897
  1162
wenzelm@12897
  1163
lemma Int_UNIV [simp]: "(A \<inter> B = UNIV) = (A = UNIV & B = UNIV)"
wenzelm@12897
  1164
  by blast
wenzelm@12897
  1165
wenzelm@12897
  1166
lemma Int_subset_iff: "(C \<subseteq> A \<inter> B) = (C \<subseteq> A & C \<subseteq> B)"
wenzelm@12897
  1167
  by blast
wenzelm@12897
  1168
wenzelm@12897
  1169
lemma Int_Collect: "(x \<in> A \<inter> {x. P x}) = (x \<in> A & P x)"
wenzelm@12897
  1170
  by blast
wenzelm@12897
  1171
wenzelm@12897
  1172
wenzelm@12897
  1173
text {* \medskip @{text Un}. *}
wenzelm@12897
  1174
wenzelm@12897
  1175
lemma Un_absorb [simp]: "A \<union> A = A"
wenzelm@12897
  1176
  by blast
wenzelm@12897
  1177
wenzelm@12897
  1178
lemma Un_left_absorb: "A \<union> (A \<union> B) = A \<union> B"
wenzelm@12897
  1179
  by blast
wenzelm@12897
  1180
wenzelm@12897
  1181
lemma Un_commute: "A \<union> B = B \<union> A"
wenzelm@12897
  1182
  by blast
wenzelm@12897
  1183
wenzelm@12897
  1184
lemma Un_left_commute: "A \<union> (B \<union> C) = B \<union> (A \<union> C)"
wenzelm@12897
  1185
  by blast
wenzelm@12897
  1186
wenzelm@12897
  1187
lemma Un_assoc: "(A \<union> B) \<union> C = A \<union> (B \<union> C)"
wenzelm@12897
  1188
  by blast
wenzelm@12897
  1189
wenzelm@12897
  1190
lemmas Un_ac = Un_assoc Un_left_absorb Un_commute Un_left_commute
wenzelm@12897
  1191
  -- {* Union is an AC-operator *}
wenzelm@12897
  1192
wenzelm@12897
  1193
lemma Un_absorb1: "A \<subseteq> B ==> A \<union> B = B"
wenzelm@12897
  1194
  by blast
wenzelm@12897
  1195
wenzelm@12897
  1196
lemma Un_absorb2: "B \<subseteq> A ==> A \<union> B = A"
wenzelm@12897
  1197
  by blast
wenzelm@12897
  1198
wenzelm@12897
  1199
lemma Un_empty_left [simp]: "{} \<union> B = B"
wenzelm@12897
  1200
  by blast
wenzelm@12897
  1201
wenzelm@12897
  1202
lemma Un_empty_right [simp]: "A \<union> {} = A"
wenzelm@12897
  1203
  by blast
wenzelm@12897
  1204
wenzelm@12897
  1205
lemma Un_UNIV_left [simp]: "UNIV \<union> B = UNIV"
wenzelm@12897
  1206
  by blast
wenzelm@12897
  1207
wenzelm@12897
  1208
lemma Un_UNIV_right [simp]: "A \<union> UNIV = UNIV"
wenzelm@12897
  1209
  by blast
wenzelm@12897
  1210
wenzelm@12897
  1211
lemma Un_eq_Union: "A \<union> B = \<Union>{A, B}"
wenzelm@12897
  1212
  by blast
wenzelm@12897
  1213
wenzelm@12897
  1214
lemma Un_insert_left [simp]: "(insert a B) \<union> C = insert a (B \<union> C)"
wenzelm@12897
  1215
  by blast
wenzelm@12897
  1216
wenzelm@12897
  1217
lemma Un_insert_right [simp]: "A \<union> (insert a B) = insert a (A \<union> B)"
wenzelm@12897
  1218
  by blast
wenzelm@12897
  1219
wenzelm@12897
  1220
lemma Int_insert_left:
wenzelm@12897
  1221
    "(insert a B) Int C = (if a \<in> C then insert a (B \<inter> C) else B \<inter> C)"
wenzelm@12897
  1222
  by auto
wenzelm@12897
  1223
wenzelm@12897
  1224
lemma Int_insert_right:
wenzelm@12897
  1225
    "A \<inter> (insert a B) = (if a \<in> A then insert a (A \<inter> B) else A \<inter> B)"
wenzelm@12897
  1226
  by auto
wenzelm@12897
  1227
wenzelm@12897
  1228
lemma Un_Int_distrib: "A \<union> (B \<inter> C) = (A \<union> B) \<inter> (A \<union> C)"
wenzelm@12897
  1229
  by blast
wenzelm@12897
  1230
wenzelm@12897
  1231
lemma Un_Int_distrib2: "(B \<inter> C) \<union> A = (B \<union> A) \<inter> (C \<union> A)"
wenzelm@12897
  1232
  by blast
wenzelm@12897
  1233
wenzelm@12897
  1234
lemma Un_Int_crazy:
wenzelm@12897
  1235
    "(A \<inter> B) \<union> (B \<inter> C) \<union> (C \<inter> A) = (A \<union> B) \<inter> (B \<union> C) \<inter> (C \<union> A)"
wenzelm@12897
  1236
  by blast
wenzelm@12897
  1237
wenzelm@12897
  1238
lemma subset_Un_eq: "(A \<subseteq> B) = (A \<union> B = B)"
wenzelm@12897
  1239
  by blast
wenzelm@12897
  1240
wenzelm@12897
  1241
lemma Un_empty [iff]: "(A \<union> B = {}) = (A = {} & B = {})"
wenzelm@12897
  1242
  by blast
wenzelm@12897
  1243
wenzelm@12897
  1244
lemma Un_subset_iff: "(A \<union> B \<subseteq> C) = (A \<subseteq> C & B \<subseteq> C)"
wenzelm@12897
  1245
  by blast
wenzelm@12897
  1246
wenzelm@12897
  1247
lemma Un_Diff_Int: "(A - B) \<union> (A \<inter> B) = A"
wenzelm@12897
  1248
  by blast
wenzelm@12897
  1249
wenzelm@12897
  1250
wenzelm@12897
  1251
text {* \medskip Set complement *}
wenzelm@12897
  1252
wenzelm@12897
  1253
lemma Compl_disjoint [simp]: "A \<inter> -A = {}"
wenzelm@12897
  1254
  by blast
wenzelm@12897
  1255
wenzelm@12897
  1256
lemma Compl_disjoint2 [simp]: "-A \<inter> A = {}"
wenzelm@12897
  1257
  by blast
wenzelm@12897
  1258
paulson@13818
  1259
lemma Compl_partition: "A \<union> -A = UNIV"
paulson@13818
  1260
  by blast
paulson@13818
  1261
paulson@13818
  1262
lemma Compl_partition2: "-A \<union> A = UNIV"
wenzelm@12897
  1263
  by blast
wenzelm@12897
  1264
wenzelm@12897
  1265
lemma double_complement [simp]: "- (-A) = (A::'a set)"
wenzelm@12897
  1266
  by blast
wenzelm@12897
  1267
wenzelm@12897
  1268
lemma Compl_Un [simp]: "-(A \<union> B) = (-A) \<inter> (-B)"
wenzelm@12897
  1269
  by blast
wenzelm@12897
  1270
wenzelm@12897
  1271
lemma Compl_Int [simp]: "-(A \<inter> B) = (-A) \<union> (-B)"
wenzelm@12897
  1272
  by blast
wenzelm@12897
  1273
wenzelm@12897
  1274
lemma Compl_UN [simp]: "-(\<Union>x\<in>A. B x) = (\<Inter>x\<in>A. -B x)"
wenzelm@12897
  1275
  by blast
wenzelm@12897
  1276
wenzelm@12897
  1277
lemma Compl_INT [simp]: "-(\<Inter>x\<in>A. B x) = (\<Union>x\<in>A. -B x)"
wenzelm@12897
  1278
  by blast
wenzelm@12897
  1279
wenzelm@12897
  1280
lemma subset_Compl_self_eq: "(A \<subseteq> -A) = (A = {})"
wenzelm@12897
  1281
  by blast
wenzelm@12897
  1282
wenzelm@12897
  1283
lemma Un_Int_assoc_eq: "((A \<inter> B) \<union> C = A \<inter> (B \<union> C)) = (C \<subseteq> A)"
wenzelm@12897
  1284
  -- {* Halmos, Naive Set Theory, page 16. *}
wenzelm@12897
  1285
  by blast
wenzelm@12897
  1286
wenzelm@12897
  1287
lemma Compl_UNIV_eq [simp]: "-UNIV = {}"
wenzelm@12897
  1288
  by blast
wenzelm@12897
  1289
wenzelm@12897
  1290
lemma Compl_empty_eq [simp]: "-{} = UNIV"
wenzelm@12897
  1291
  by blast
wenzelm@12897
  1292
wenzelm@12897
  1293
lemma Compl_subset_Compl_iff [iff]: "(-A \<subseteq> -B) = (B \<subseteq> A)"
wenzelm@12897
  1294
  by blast
wenzelm@12897
  1295
wenzelm@12897
  1296
lemma Compl_eq_Compl_iff [iff]: "(-A = -B) = (A = (B::'a set))"
wenzelm@12897
  1297
  by blast
wenzelm@12897
  1298
wenzelm@12897
  1299
wenzelm@12897
  1300
text {* \medskip @{text Union}. *}
wenzelm@12897
  1301
wenzelm@12897
  1302
lemma Union_empty [simp]: "Union({}) = {}"
wenzelm@12897
  1303
  by blast
wenzelm@12897
  1304
wenzelm@12897
  1305
lemma Union_UNIV [simp]: "Union UNIV = UNIV"
wenzelm@12897
  1306
  by blast
wenzelm@12897
  1307
wenzelm@12897
  1308
lemma Union_insert [simp]: "Union (insert a B) = a \<union> \<Union>B"
wenzelm@12897
  1309
  by blast
wenzelm@12897
  1310
wenzelm@12897
  1311
lemma Union_Un_distrib [simp]: "\<Union>(A Un B) = \<Union>A \<union> \<Union>B"
wenzelm@12897
  1312
  by blast
wenzelm@12897
  1313
wenzelm@12897
  1314
lemma Union_Int_subset: "\<Union>(A \<inter> B) \<subseteq> \<Union>A \<inter> \<Union>B"
wenzelm@12897
  1315
  by blast
wenzelm@12897
  1316
wenzelm@12897
  1317
lemma Union_empty_conv [iff]: "(\<Union>A = {}) = (\<forall>x\<in>A. x = {})"
nipkow@13653
  1318
  by blast
nipkow@13653
  1319
nipkow@13653
  1320
lemma empty_Union_conv [iff]: "({} = \<Union>A) = (\<forall>x\<in>A. x = {})"
nipkow@13653
  1321
  by blast
wenzelm@12897
  1322
wenzelm@12897
  1323
lemma Union_disjoint: "(\<Union>C \<inter> A = {}) = (\<forall>B\<in>C. B \<inter> A = {})"
wenzelm@12897
  1324
  by blast
wenzelm@12897
  1325
wenzelm@12897
  1326
wenzelm@12897
  1327
text {* \medskip @{text Inter}. *}
wenzelm@12897
  1328
wenzelm@12897
  1329
lemma Inter_empty [simp]: "\<Inter>{} = UNIV"
wenzelm@12897
  1330
  by blast
wenzelm@12897
  1331
wenzelm@12897
  1332
lemma Inter_UNIV [simp]: "\<Inter>UNIV = {}"
wenzelm@12897
  1333
  by blast
wenzelm@12897
  1334
wenzelm@12897
  1335
lemma Inter_insert [simp]: "\<Inter>(insert a B) = a \<inter> \<Inter>B"
wenzelm@12897
  1336
  by blast
wenzelm@12897
  1337
wenzelm@12897
  1338
lemma Inter_Un_subset: "\<Inter>A \<union> \<Inter>B \<subseteq> \<Inter>(A \<inter> B)"
wenzelm@12897
  1339
  by blast
wenzelm@12897
  1340
wenzelm@12897
  1341
lemma Inter_Un_distrib: "\<Inter>(A \<union> B) = \<Inter>A \<inter> \<Inter>B"
wenzelm@12897
  1342
  by blast
wenzelm@12897
  1343
nipkow@13653
  1344
lemma Inter_UNIV_conv [iff]:
nipkow@13653
  1345
  "(\<Inter>A = UNIV) = (\<forall>x\<in>A. x = UNIV)"
nipkow@13653
  1346
  "(UNIV = \<Inter>A) = (\<forall>x\<in>A. x = UNIV)"
nipkow@13653
  1347
  by(blast)+
nipkow@13653
  1348
wenzelm@12897
  1349
wenzelm@12897
  1350
text {*
wenzelm@12897
  1351
  \medskip @{text UN} and @{text INT}.
wenzelm@12897
  1352
wenzelm@12897
  1353
  Basic identities: *}
wenzelm@12897
  1354
wenzelm@12897
  1355
lemma UN_empty [simp]: "(\<Union>x\<in>{}. B x) = {}"
wenzelm@12897
  1356
  by blast
wenzelm@12897
  1357
wenzelm@12897
  1358
lemma UN_empty2 [simp]: "(\<Union>x\<in>A. {}) = {}"
wenzelm@12897
  1359
  by blast
wenzelm@12897
  1360
wenzelm@12897
  1361
lemma UN_singleton [simp]: "(\<Union>x\<in>A. {x}) = A"
wenzelm@12897
  1362
  by blast
wenzelm@12897
  1363
wenzelm@12897
  1364
lemma UN_absorb: "k \<in> I ==> A k \<union> (\<Union>i\<in>I. A i) = (\<Union>i\<in>I. A i)"
wenzelm@12897
  1365
  by blast
wenzelm@12897
  1366
wenzelm@12897
  1367
lemma INT_empty [simp]: "(\<Inter>x\<in>{}. B x) = UNIV"
wenzelm@12897
  1368
  by blast
wenzelm@12897
  1369
wenzelm@12897
  1370
lemma INT_absorb: "k \<in> I ==> A k \<inter> (\<Inter>i\<in>I. A i) = (\<Inter>i\<in>I. A i)"
wenzelm@12897
  1371
  by blast
wenzelm@12897
  1372
wenzelm@12897
  1373
lemma UN_insert [simp]: "(\<Union>x\<in>insert a A. B x) = B a \<union> UNION A B"
wenzelm@12897
  1374
  by blast
wenzelm@12897
  1375
wenzelm@12897
  1376
lemma UN_Un: "(\<Union>i \<in> A \<union> B. M i) = (\<Union>i\<in>A. M i) \<union> (\<Union>i\<in>B. M i)"
wenzelm@12897
  1377
  by blast
wenzelm@12897
  1378
wenzelm@12897
  1379
lemma UN_UN_flatten: "(\<Union>x \<in> (\<Union>y\<in>A. B y). C x) = (\<Union>y\<in>A. \<Union>x\<in>B y. C x)"
wenzelm@12897
  1380
  by blast
wenzelm@12897
  1381
wenzelm@12897
  1382
lemma UN_subset_iff: "((\<Union>i\<in>I. A i) \<subseteq> B) = (\<forall>i\<in>I. A i \<subseteq> B)"
wenzelm@12897
  1383
  by blast
wenzelm@12897
  1384
wenzelm@12897
  1385
lemma INT_subset_iff: "(B \<subseteq> (\<Inter>i\<in>I. A i)) = (\<forall>i\<in>I. B \<subseteq> A i)"
wenzelm@12897
  1386
  by blast
wenzelm@12897
  1387
wenzelm@12897
  1388
lemma INT_insert [simp]: "(\<Inter>x \<in> insert a A. B x) = B a \<inter> INTER A B"
wenzelm@12897
  1389
  by blast
wenzelm@12897
  1390
wenzelm@12897
  1391
lemma INT_Un: "(\<Inter>i \<in> A \<union> B. M i) = (\<Inter>i \<in> A. M i) \<inter> (\<Inter>i\<in>B. M i)"
wenzelm@12897
  1392
  by blast
wenzelm@12897
  1393
wenzelm@12897
  1394
lemma INT_insert_distrib:
wenzelm@12897
  1395
    "u \<in> A ==> (\<Inter>x\<in>A. insert a (B x)) = insert a (\<Inter>x\<in>A. B x)"
wenzelm@12897
  1396
  by blast
wenzelm@12897
  1397
wenzelm@12897
  1398
lemma Union_image_eq [simp]: "\<Union>(B`A) = (\<Union>x\<in>A. B x)"
wenzelm@12897
  1399
  by blast
wenzelm@12897
  1400
wenzelm@12897
  1401
lemma image_Union: "f ` \<Union>S = (\<Union>x\<in>S. f ` x)"
wenzelm@12897
  1402
  by blast
wenzelm@12897
  1403
wenzelm@12897
  1404
lemma Inter_image_eq [simp]: "\<Inter>(B`A) = (\<Inter>x\<in>A. B x)"
wenzelm@12897
  1405
  by blast
wenzelm@12897
  1406
wenzelm@12897
  1407
lemma UN_constant [simp]: "(\<Union>y\<in>A. c) = (if A = {} then {} else c)"
wenzelm@12897
  1408
  by auto
wenzelm@12897
  1409
wenzelm@12897
  1410
lemma INT_constant [simp]: "(\<Inter>y\<in>A. c) = (if A = {} then UNIV else c)"
wenzelm@12897
  1411
  by auto
wenzelm@12897
  1412
wenzelm@12897
  1413
lemma UN_eq: "(\<Union>x\<in>A. B x) = \<Union>({Y. \<exists>x\<in>A. Y = B x})"
wenzelm@12897
  1414
  by blast
wenzelm@12897
  1415
wenzelm@12897
  1416
lemma INT_eq: "(\<Inter>x\<in>A. B x) = \<Inter>({Y. \<exists>x\<in>A. Y = B x})"
wenzelm@12897
  1417
  -- {* Look: it has an \emph{existential} quantifier *}
wenzelm@12897
  1418
  by blast
wenzelm@12897
  1419
nipkow@13653
  1420
lemma UNION_empty_conv[iff]:
nipkow@13653
  1421
  "({} = (UN x:A. B x)) = (\<forall>x\<in>A. B x = {})"
nipkow@13653
  1422
  "((UN x:A. B x) = {}) = (\<forall>x\<in>A. B x = {})"
nipkow@13653
  1423
by blast+
nipkow@13653
  1424
nipkow@13653
  1425
lemma INTER_UNIV_conv[iff]:
nipkow@13653
  1426
 "(UNIV = (INT x:A. B x)) = (\<forall>x\<in>A. B x = UNIV)"
nipkow@13653
  1427
 "((INT x:A. B x) = UNIV) = (\<forall>x\<in>A. B x = UNIV)"
nipkow@13653
  1428
by blast+
wenzelm@12897
  1429
wenzelm@12897
  1430
wenzelm@12897
  1431
text {* \medskip Distributive laws: *}
wenzelm@12897
  1432
wenzelm@12897
  1433
lemma Int_Union: "A \<inter> \<Union>B = (\<Union>C\<in>B. A \<inter> C)"
wenzelm@12897
  1434
  by blast
wenzelm@12897
  1435
wenzelm@12897
  1436
lemma Int_Union2: "\<Union>B \<inter> A = (\<Union>C\<in>B. C \<inter> A)"
wenzelm@12897
  1437
  by blast
wenzelm@12897
  1438
wenzelm@12897
  1439
lemma Un_Union_image: "(\<Union>x\<in>C. A x \<union> B x) = \<Union>(A`C) \<union> \<Union>(B`C)"
wenzelm@12897
  1440
  -- {* Devlin, Fundamentals of Contemporary Set Theory, page 12, exercise 5: *}
wenzelm@12897
  1441
  -- {* Union of a family of unions *}
wenzelm@12897
  1442
  by blast
wenzelm@12897
  1443
wenzelm@12897
  1444
lemma UN_Un_distrib: "(\<Union>i\<in>I. A i \<union> B i) = (\<Union>i\<in>I. A i) \<union> (\<Union>i\<in>I. B i)"
wenzelm@12897
  1445
  -- {* Equivalent version *}
wenzelm@12897
  1446
  by blast
wenzelm@12897
  1447
wenzelm@12897
  1448
lemma Un_Inter: "A \<union> \<Inter>B = (\<Inter>C\<in>B. A \<union> C)"
wenzelm@12897
  1449
  by blast
wenzelm@12897
  1450
wenzelm@12897
  1451
lemma Int_Inter_image: "(\<Inter>x\<in>C. A x \<inter> B x) = \<Inter>(A`C) \<inter> \<Inter>(B`C)"
wenzelm@12897
  1452
  by blast
wenzelm@12897
  1453
wenzelm@12897
  1454
lemma INT_Int_distrib: "(\<Inter>i\<in>I. A i \<inter> B i) = (\<Inter>i\<in>I. A i) \<inter> (\<Inter>i\<in>I. B i)"
wenzelm@12897
  1455
  -- {* Equivalent version *}
wenzelm@12897
  1456
  by blast
wenzelm@12897
  1457
wenzelm@12897
  1458
lemma Int_UN_distrib: "B \<inter> (\<Union>i\<in>I. A i) = (\<Union>i\<in>I. B \<inter> A i)"
wenzelm@12897
  1459
  -- {* Halmos, Naive Set Theory, page 35. *}
wenzelm@12897
  1460
  by blast
wenzelm@12897
  1461
wenzelm@12897
  1462
lemma Un_INT_distrib: "B \<union> (\<Inter>i\<in>I. A i) = (\<Inter>i\<in>I. B \<union> A i)"
wenzelm@12897
  1463
  by blast
wenzelm@12897
  1464
wenzelm@12897
  1465
lemma Int_UN_distrib2: "(\<Union>i\<in>I. A i) \<inter> (\<Union>j\<in>J. B j) = (\<Union>i\<in>I. \<Union>j\<in>J. A i \<inter> B j)"
wenzelm@12897
  1466
  by blast
wenzelm@12897
  1467
wenzelm@12897
  1468
lemma Un_INT_distrib2: "(\<Inter>i\<in>I. A i) \<union> (\<Inter>j\<in>J. B j) = (\<Inter>i\<in>I. \<Inter>j\<in>J. A i \<union> B j)"
wenzelm@12897
  1469
  by blast
wenzelm@12897
  1470
wenzelm@12897
  1471
wenzelm@12897
  1472
text {* \medskip Bounded quantifiers.
wenzelm@12897
  1473
wenzelm@12897
  1474
  The following are not added to the default simpset because
wenzelm@12897
  1475
  (a) they duplicate the body and (b) there are no similar rules for @{text Int}. *}
wenzelm@12897
  1476
wenzelm@12897
  1477
lemma ball_Un: "(\<forall>x \<in> A \<union> B. P x) = ((\<forall>x\<in>A. P x) & (\<forall>x\<in>B. P x))"
wenzelm@12897
  1478
  by blast
wenzelm@12897
  1479
wenzelm@12897
  1480
lemma bex_Un: "(\<exists>x \<in> A \<union> B. P x) = ((\<exists>x\<in>A. P x) | (\<exists>x\<in>B. P x))"
wenzelm@12897
  1481
  by blast
wenzelm@12897
  1482
wenzelm@12897
  1483
lemma ball_UN: "(\<forall>z \<in> UNION A B. P z) = (\<forall>x\<in>A. \<forall>z \<in> B x. P z)"
wenzelm@12897
  1484
  by blast
wenzelm@12897
  1485
wenzelm@12897
  1486
lemma bex_UN: "(\<exists>z \<in> UNION A B. P z) = (\<exists>x\<in>A. \<exists>z\<in>B x. P z)"
wenzelm@12897
  1487
  by blast
wenzelm@12897
  1488
wenzelm@12897
  1489
wenzelm@12897
  1490
text {* \medskip Set difference. *}
wenzelm@12897
  1491
wenzelm@12897
  1492
lemma Diff_eq: "A - B = A \<inter> (-B)"
wenzelm@12897
  1493
  by blast
wenzelm@12897
  1494
wenzelm@12897
  1495
lemma Diff_eq_empty_iff [simp]: "(A - B = {}) = (A \<subseteq> B)"
wenzelm@12897
  1496
  by blast
wenzelm@12897
  1497
wenzelm@12897
  1498
lemma Diff_cancel [simp]: "A - A = {}"
wenzelm@12897
  1499
  by blast
wenzelm@12897
  1500
wenzelm@12897
  1501
lemma Diff_triv: "A \<inter> B = {} ==> A - B = A"
wenzelm@12897
  1502
  by (blast elim: equalityE)
wenzelm@12897
  1503
wenzelm@12897
  1504
lemma empty_Diff [simp]: "{} - A = {}"
wenzelm@12897
  1505
  by blast
wenzelm@12897
  1506
wenzelm@12897
  1507
lemma Diff_empty [simp]: "A - {} = A"
wenzelm@12897
  1508
  by blast
wenzelm@12897
  1509
wenzelm@12897
  1510
lemma Diff_UNIV [simp]: "A - UNIV = {}"
wenzelm@12897
  1511
  by blast
wenzelm@12897
  1512
wenzelm@12897
  1513
lemma Diff_insert0 [simp]: "x \<notin> A ==> A - insert x B = A - B"
wenzelm@12897
  1514
  by blast
wenzelm@12897
  1515
wenzelm@12897
  1516
lemma Diff_insert: "A - insert a B = A - B - {a}"
wenzelm@12897
  1517
  -- {* NOT SUITABLE FOR REWRITING since @{text "{a} == insert a 0"} *}
wenzelm@12897
  1518
  by blast
wenzelm@12897
  1519
wenzelm@12897
  1520
lemma Diff_insert2: "A - insert a B = A - {a} - B"
wenzelm@12897
  1521
  -- {* NOT SUITABLE FOR REWRITING since @{text "{a} == insert a 0"} *}
wenzelm@12897
  1522
  by blast
wenzelm@12897
  1523
wenzelm@12897
  1524
lemma insert_Diff_if: "insert x A - B = (if x \<in> B then A - B else insert x (A - B))"
wenzelm@12897
  1525
  by auto
wenzelm@12897
  1526
wenzelm@12897
  1527
lemma insert_Diff1 [simp]: "x \<in> B ==> insert x A - B = A - B"
wenzelm@12897
  1528
  by blast
wenzelm@12897
  1529
wenzelm@12897
  1530
lemma insert_Diff: "a \<in> A ==> insert a (A - {a}) = A"
wenzelm@12897
  1531
  by blast
wenzelm@12897
  1532
wenzelm@12897
  1533
lemma Diff_insert_absorb: "x \<notin> A ==> (insert x A) - {x} = A"
wenzelm@12897
  1534
  by auto
wenzelm@12897
  1535
wenzelm@12897
  1536
lemma Diff_disjoint [simp]: "A \<inter> (B - A) = {}"
wenzelm@12897
  1537
  by blast
wenzelm@12897
  1538
wenzelm@12897
  1539
lemma Diff_partition: "A \<subseteq> B ==> A \<union> (B - A) = B"
wenzelm@12897
  1540
  by blast
wenzelm@12897
  1541
wenzelm@12897
  1542
lemma double_diff: "A \<subseteq> B ==> B \<subseteq> C ==> B - (C - A) = A"
wenzelm@12897
  1543
  by blast
wenzelm@12897
  1544
wenzelm@12897
  1545
lemma Un_Diff_cancel [simp]: "A \<union> (B - A) = A \<union> B"
wenzelm@12897
  1546
  by blast
wenzelm@12897
  1547
wenzelm@12897
  1548
lemma Un_Diff_cancel2 [simp]: "(B - A) \<union> A = B \<union> A"
wenzelm@12897
  1549
  by blast
wenzelm@12897
  1550
wenzelm@12897
  1551
lemma Diff_Un: "A - (B \<union> C) = (A - B) \<inter> (A - C)"
wenzelm@12897
  1552
  by blast
wenzelm@12897
  1553
wenzelm@12897
  1554
lemma Diff_Int: "A - (B \<inter> C) = (A - B) \<union> (A - C)"
wenzelm@12897
  1555
  by blast
wenzelm@12897
  1556
wenzelm@12897
  1557
lemma Un_Diff: "(A \<union> B) - C = (A - C) \<union> (B - C)"
wenzelm@12897
  1558
  by blast
wenzelm@12897
  1559
wenzelm@12897
  1560
lemma Int_Diff: "(A \<inter> B) - C = A \<inter> (B - C)"
wenzelm@12897
  1561
  by blast
wenzelm@12897
  1562
wenzelm@12897
  1563
lemma Diff_Int_distrib: "C \<inter> (A - B) = (C \<inter> A) - (C \<inter> B)"
wenzelm@12897
  1564
  by blast
wenzelm@12897
  1565
wenzelm@12897
  1566
lemma Diff_Int_distrib2: "(A - B) \<inter> C = (A \<inter> C) - (B \<inter> C)"
wenzelm@12897
  1567
  by blast
wenzelm@12897
  1568
wenzelm@12897
  1569
lemma Diff_Compl [simp]: "A - (- B) = A \<inter> B"
wenzelm@12897
  1570
  by auto
wenzelm@12897
  1571
wenzelm@12897
  1572
lemma Compl_Diff_eq [simp]: "- (A - B) = -A \<union> B"
wenzelm@12897
  1573
  by blast
wenzelm@12897
  1574
wenzelm@12897
  1575
wenzelm@12897
  1576
text {* \medskip Quantification over type @{typ bool}. *}
wenzelm@12897
  1577
wenzelm@12897
  1578
lemma all_bool_eq: "(\<forall>b::bool. P b) = (P True & P False)"
wenzelm@12897
  1579
  apply auto
wenzelm@12897
  1580
  apply (tactic {* case_tac "b" 1 *})
wenzelm@12897
  1581
   apply auto
wenzelm@12897
  1582
  done
wenzelm@12897
  1583
wenzelm@12897
  1584
lemma bool_induct: "P True \<Longrightarrow> P False \<Longrightarrow> P x"
wenzelm@12897
  1585
  by (rule conjI [THEN all_bool_eq [THEN iffD2], THEN spec])
wenzelm@12897
  1586
wenzelm@12897
  1587
lemma ex_bool_eq: "(\<exists>b::bool. P b) = (P True | P False)"
wenzelm@12897
  1588
  apply auto
wenzelm@12897
  1589
  apply (tactic {* case_tac "b" 1 *})
wenzelm@12897
  1590
   apply auto
wenzelm@12897
  1591
  done
wenzelm@12897
  1592
wenzelm@12897
  1593
lemma Un_eq_UN: "A \<union> B = (\<Union>b. if b then A else B)"
wenzelm@12897
  1594
  by (auto simp add: split_if_mem2)
wenzelm@12897
  1595
wenzelm@12897
  1596
lemma UN_bool_eq: "(\<Union>b::bool. A b) = (A True \<union> A False)"
wenzelm@12897
  1597
  apply auto
wenzelm@12897
  1598
  apply (tactic {* case_tac "b" 1 *})
wenzelm@12897
  1599
   apply auto
wenzelm@12897
  1600
  done
wenzelm@12897
  1601
wenzelm@12897
  1602
lemma INT_bool_eq: "(\<Inter>b::bool. A b) = (A True \<inter> A False)"
wenzelm@12897
  1603
  apply auto
wenzelm@12897
  1604
  apply (tactic {* case_tac "b" 1 *})
wenzelm@12897
  1605
  apply auto
wenzelm@12897
  1606
  done
wenzelm@12897
  1607
wenzelm@12897
  1608
wenzelm@12897
  1609
text {* \medskip @{text Pow} *}
wenzelm@12897
  1610
wenzelm@12897
  1611
lemma Pow_empty [simp]: "Pow {} = {{}}"
wenzelm@12897
  1612
  by (auto simp add: Pow_def)
wenzelm@12897
  1613
wenzelm@12897
  1614
lemma Pow_insert: "Pow (insert a A) = Pow A \<union> (insert a ` Pow A)"
wenzelm@12897
  1615
  by (blast intro: image_eqI [where ?x = "u - {a}", standard])
wenzelm@12897
  1616
wenzelm@12897
  1617
lemma Pow_Compl: "Pow (- A) = {-B | B. A \<in> Pow B}"
wenzelm@12897
  1618
  by (blast intro: exI [where ?x = "- u", standard])
wenzelm@12897
  1619
wenzelm@12897
  1620
lemma Pow_UNIV [simp]: "Pow UNIV = UNIV"
wenzelm@12897
  1621
  by blast
wenzelm@12897
  1622
wenzelm@12897
  1623
lemma Un_Pow_subset: "Pow A \<union> Pow B \<subseteq> Pow (A \<union> B)"
wenzelm@12897
  1624
  by blast
wenzelm@12897
  1625
wenzelm@12897
  1626
lemma UN_Pow_subset: "(\<Union>x\<in>A. Pow (B x)) \<subseteq> Pow (\<Union>x\<in>A. B x)"
wenzelm@12897
  1627
  by blast
wenzelm@12897
  1628
wenzelm@12897
  1629
lemma subset_Pow_Union: "A \<subseteq> Pow (\<Union>A)"
wenzelm@12897
  1630
  by blast
wenzelm@12897
  1631
wenzelm@12897
  1632
lemma Union_Pow_eq [simp]: "\<Union>(Pow A) = A"
wenzelm@12897
  1633
  by blast
wenzelm@12897
  1634
wenzelm@12897
  1635
lemma Pow_Int_eq [simp]: "Pow (A \<inter> B) = Pow A \<inter> Pow B"
wenzelm@12897
  1636
  by blast
wenzelm@12897
  1637
wenzelm@12897
  1638
lemma Pow_INT_eq: "Pow (\<Inter>x\<in>A. B x) = (\<Inter>x\<in>A. Pow (B x))"
wenzelm@12897
  1639
  by blast
wenzelm@12897
  1640
wenzelm@12897
  1641
wenzelm@12897
  1642
text {* \medskip Miscellany. *}
wenzelm@12897
  1643
wenzelm@12897
  1644
lemma set_eq_subset: "(A = B) = (A \<subseteq> B & B \<subseteq> A)"
wenzelm@12897
  1645
  by blast
wenzelm@12897
  1646
wenzelm@12897
  1647
lemma subset_iff: "(A \<subseteq> B) = (\<forall>t. t \<in> A --> t \<in> B)"
wenzelm@12897
  1648
  by blast
wenzelm@12897
  1649
wenzelm@12897
  1650
lemma subset_iff_psubset_eq: "(A \<subseteq> B) = ((A \<subset> B) | (A = B))"
wenzelm@12897
  1651
  by (unfold psubset_def) blast
wenzelm@12897
  1652
wenzelm@12897
  1653
lemma all_not_in_conv [iff]: "(\<forall>x. x \<notin> A) = (A = {})"
wenzelm@12897
  1654
  by blast
wenzelm@12897
  1655
paulson@13831
  1656
lemma ex_in_conv: "(\<exists>x. x \<in> A) = (A \<noteq> {})"
paulson@13831
  1657
  by blast
paulson@13831
  1658
wenzelm@12897
  1659
lemma distinct_lemma: "f x \<noteq> f y ==> x \<noteq> y"
wenzelm@12897
  1660
  by rules
wenzelm@12897
  1661
wenzelm@12897
  1662
paulson@13860
  1663
text {* \medskip Miniscoping: pushing in quantifiers and big Unions
paulson@13860
  1664
           and Intersections. *}
wenzelm@12897
  1665
wenzelm@12897
  1666
lemma UN_simps [simp]:
wenzelm@12897
  1667
  "!!a B C. (UN x:C. insert a (B x)) = (if C={} then {} else insert a (UN x:C. B x))"
wenzelm@12897
  1668
  "!!A B C. (UN x:C. A x Un B)   = ((if C={} then {} else (UN x:C. A x) Un B))"
wenzelm@12897
  1669
  "!!A B C. (UN x:C. A Un B x)   = ((if C={} then {} else A Un (UN x:C. B x)))"
wenzelm@12897
  1670
  "!!A B C. (UN x:C. A x Int B)  = ((UN x:C. A x) Int B)"
wenzelm@12897
  1671
  "!!A B C. (UN x:C. A Int B x)  = (A Int (UN x:C. B x))"
wenzelm@12897
  1672
  "!!A B C. (UN x:C. A x - B)    = ((UN x:C. A x) - B)"
wenzelm@12897
  1673
  "!!A B C. (UN x:C. A - B x)    = (A - (INT x:C. B x))"
wenzelm@12897
  1674
  "!!A B. (UN x: Union A. B x) = (UN y:A. UN x:y. B x)"
wenzelm@12897
  1675
  "!!A B C. (UN z: UNION A B. C z) = (UN  x:A. UN z: B(x). C z)"
wenzelm@12897
  1676
  "!!A B f. (UN x:f`A. B x)     = (UN a:A. B (f a))"
wenzelm@12897
  1677
  by auto
wenzelm@12897
  1678
wenzelm@12897
  1679
lemma INT_simps [simp]:
wenzelm@12897
  1680
  "!!A B C. (INT x:C. A x Int B) = (if C={} then UNIV else (INT x:C. A x) Int B)"
wenzelm@12897
  1681
  "!!A B C. (INT x:C. A Int B x) = (if C={} then UNIV else A Int (INT x:C. B x))"
wenzelm@12897
  1682
  "!!A B C. (INT x:C. A x - B)   = (if C={} then UNIV else (INT x:C. A x) - B)"
wenzelm@12897
  1683
  "!!A B C. (INT x:C. A - B x)   = (if C={} then UNIV else A - (UN x:C. B x))"
wenzelm@12897
  1684
  "!!a B C. (INT x:C. insert a (B x)) = insert a (INT x:C. B x)"
wenzelm@12897
  1685
  "!!A B C. (INT x:C. A x Un B)  = ((INT x:C. A x) Un B)"
wenzelm@12897
  1686
  "!!A B C. (INT x:C. A Un B x)  = (A Un (INT x:C. B x))"
wenzelm@12897
  1687
  "!!A B. (INT x: Union A. B x) = (INT y:A. INT x:y. B x)"
wenzelm@12897
  1688
  "!!A B C. (INT z: UNION A B. C z) = (INT x:A. INT z: B(x). C z)"
wenzelm@12897
  1689
  "!!A B f. (INT x:f`A. B x)    = (INT a:A. B (f a))"
wenzelm@12897
  1690
  by auto
wenzelm@12897
  1691
wenzelm@12897
  1692
lemma ball_simps [simp]:
wenzelm@12897
  1693
  "!!A P Q. (ALL x:A. P x | Q) = ((ALL x:A. P x) | Q)"
wenzelm@12897
  1694
  "!!A P Q. (ALL x:A. P | Q x) = (P | (ALL x:A. Q x))"
wenzelm@12897
  1695
  "!!A P Q. (ALL x:A. P --> Q x) = (P --> (ALL x:A. Q x))"
wenzelm@12897
  1696
  "!!A P Q. (ALL x:A. P x --> Q) = ((EX x:A. P x) --> Q)"
wenzelm@12897
  1697
  "!!P. (ALL x:{}. P x) = True"
wenzelm@12897
  1698
  "!!P. (ALL x:UNIV. P x) = (ALL x. P x)"
wenzelm@12897
  1699
  "!!a B P. (ALL x:insert a B. P x) = (P a & (ALL x:B. P x))"
wenzelm@12897
  1700
  "!!A P. (ALL x:Union A. P x) = (ALL y:A. ALL x:y. P x)"
wenzelm@12897
  1701
  "!!A B P. (ALL x: UNION A B. P x) = (ALL a:A. ALL x: B a. P x)"
wenzelm@12897
  1702
  "!!P Q. (ALL x:Collect Q. P x) = (ALL x. Q x --> P x)"
wenzelm@12897
  1703
  "!!A P f. (ALL x:f`A. P x) = (ALL x:A. P (f x))"
wenzelm@12897
  1704
  "!!A P. (~(ALL x:A. P x)) = (EX x:A. ~P x)"
wenzelm@12897
  1705
  by auto
wenzelm@12897
  1706
wenzelm@12897
  1707
lemma bex_simps [simp]:
wenzelm@12897
  1708
  "!!A P Q. (EX x:A. P x & Q) = ((EX x:A. P x) & Q)"
wenzelm@12897
  1709
  "!!A P Q. (EX x:A. P & Q x) = (P & (EX x:A. Q x))"
wenzelm@12897
  1710
  "!!P. (EX x:{}. P x) = False"
wenzelm@12897
  1711
  "!!P. (EX x:UNIV. P x) = (EX x. P x)"
wenzelm@12897
  1712
  "!!a B P. (EX x:insert a B. P x) = (P(a) | (EX x:B. P x))"
wenzelm@12897
  1713
  "!!A P. (EX x:Union A. P x) = (EX y:A. EX x:y. P x)"
wenzelm@12897
  1714
  "!!A B P. (EX x: UNION A B. P x) = (EX a:A. EX x:B a. P x)"
wenzelm@12897
  1715
  "!!P Q. (EX x:Collect Q. P x) = (EX x. Q x & P x)"
wenzelm@12897
  1716
  "!!A P f. (EX x:f`A. P x) = (EX x:A. P (f x))"
wenzelm@12897
  1717
  "!!A P. (~(EX x:A. P x)) = (ALL x:A. ~P x)"
wenzelm@12897
  1718
  by auto
wenzelm@12897
  1719
wenzelm@12897
  1720
lemma ball_conj_distrib:
wenzelm@12897
  1721
  "(ALL x:A. P x & Q x) = ((ALL x:A. P x) & (ALL x:A. Q x))"
wenzelm@12897
  1722
  by blast
wenzelm@12897
  1723
wenzelm@12897
  1724
lemma bex_disj_distrib:
wenzelm@12897
  1725
  "(EX x:A. P x | Q x) = ((EX x:A. P x) | (EX x:A. Q x))"
wenzelm@12897
  1726
  by blast
wenzelm@12897
  1727
wenzelm@12897
  1728
paulson@13860
  1729
text {* \medskip Maxiscoping: pulling out big Unions and Intersections. *}
paulson@13860
  1730
paulson@13860
  1731
lemma UN_extend_simps:
paulson@13860
  1732
  "!!a B C. insert a (UN x:C. B x) = (if C={} then {a} else (UN x:C. insert a (B x)))"
paulson@13860
  1733
  "!!A B C. (UN x:C. A x) Un B    = (if C={} then B else (UN x:C. A x Un B))"
paulson@13860
  1734
  "!!A B C. A Un (UN x:C. B x)   = (if C={} then A else (UN x:C. A Un B x))"
paulson@13860
  1735
  "!!A B C. ((UN x:C. A x) Int B) = (UN x:C. A x Int B)"
paulson@13860
  1736
  "!!A B C. (A Int (UN x:C. B x)) = (UN x:C. A Int B x)"
paulson@13860
  1737
  "!!A B C. ((UN x:C. A x) - B) = (UN x:C. A x - B)"
paulson@13860
  1738
  "!!A B C. (A - (INT x:C. B x)) = (UN x:C. A - B x)"
paulson@13860
  1739
  "!!A B. (UN y:A. UN x:y. B x) = (UN x: Union A. B x)"
paulson@13860
  1740
  "!!A B C. (UN  x:A. UN z: B(x). C z) = (UN z: UNION A B. C z)"
paulson@13860
  1741
  "!!A B f. (UN a:A. B (f a)) = (UN x:f`A. B x)"
paulson@13860
  1742
  by auto
paulson@13860
  1743
paulson@13860
  1744
lemma INT_extend_simps:
paulson@13860
  1745
  "!!A B C. (INT x:C. A x) Int B = (if C={} then B else (INT x:C. A x Int B))"
paulson@13860
  1746
  "!!A B C. A Int (INT x:C. B x) = (if C={} then A else (INT x:C. A Int B x))"
paulson@13860
  1747
  "!!A B C. (INT x:C. A x) - B   = (if C={} then UNIV-B else (INT x:C. A x - B))"
paulson@13860
  1748
  "!!A B C. A - (UN x:C. B x)   = (if C={} then A else (INT x:C. A - B x))"
paulson@13860
  1749
  "!!a B C. insert a (INT x:C. B x) = (INT x:C. insert a (B x))"
paulson@13860
  1750
  "!!A B C. ((INT x:C. A x) Un B)  = (INT x:C. A x Un B)"
paulson@13860
  1751
  "!!A B C. A Un (INT x:C. B x)  = (INT x:C. A Un B x)"
paulson@13860
  1752
  "!!A B. (INT y:A. INT x:y. B x) = (INT x: Union A. B x)"
paulson@13860
  1753
  "!!A B C. (INT x:A. INT z: B(x). C z) = (INT z: UNION A B. C z)"
paulson@13860
  1754
  "!!A B f. (INT a:A. B (f a))    = (INT x:f`A. B x)"
paulson@13860
  1755
  by auto
paulson@13860
  1756
paulson@13860
  1757
wenzelm@12897
  1758
subsubsection {* Monotonicity of various operations *}
wenzelm@12897
  1759
wenzelm@12897
  1760
lemma image_mono: "A \<subseteq> B ==> f`A \<subseteq> f`B"
wenzelm@12897
  1761
  by blast
wenzelm@12897
  1762
wenzelm@12897
  1763
lemma Pow_mono: "A \<subseteq> B ==> Pow A \<subseteq> Pow B"
wenzelm@12897
  1764
  by blast
wenzelm@12897
  1765
wenzelm@12897
  1766
lemma Union_mono: "A \<subseteq> B ==> \<Union>A \<subseteq> \<Union>B"
wenzelm@12897
  1767
  by blast
wenzelm@12897
  1768
wenzelm@12897
  1769
lemma Inter_anti_mono: "B \<subseteq> A ==> \<Inter>A \<subseteq> \<Inter>B"
wenzelm@12897
  1770
  by blast
wenzelm@12897
  1771
wenzelm@12897
  1772
lemma UN_mono:
wenzelm@12897
  1773
  "A \<subseteq> B ==> (!!x. x \<in> A ==> f x \<subseteq> g x) ==>
wenzelm@12897
  1774
    (\<Union>x\<in>A. f x) \<subseteq> (\<Union>x\<in>B. g x)"
wenzelm@12897
  1775
  by (blast dest: subsetD)
wenzelm@12897
  1776
wenzelm@12897
  1777
lemma INT_anti_mono:
wenzelm@12897
  1778
  "B \<subseteq> A ==> (!!x. x \<in> A ==> f x \<subseteq> g x) ==>
wenzelm@12897
  1779
    (\<Inter>x\<in>A. f x) \<subseteq> (\<Inter>x\<in>A. g x)"
wenzelm@12897
  1780
  -- {* The last inclusion is POSITIVE! *}
wenzelm@12897
  1781
  by (blast dest: subsetD)
wenzelm@12897
  1782
wenzelm@12897
  1783
lemma insert_mono: "C \<subseteq> D ==> insert a C \<subseteq> insert a D"
wenzelm@12897
  1784
  by blast
wenzelm@12897
  1785
wenzelm@12897
  1786
lemma Un_mono: "A \<subseteq> C ==> B \<subseteq> D ==> A \<union> B \<subseteq> C \<union> D"
wenzelm@12897
  1787
  by blast
wenzelm@12897
  1788
wenzelm@12897
  1789
lemma Int_mono: "A \<subseteq> C ==> B \<subseteq> D ==> A \<inter> B \<subseteq> C \<inter> D"
wenzelm@12897
  1790
  by blast
wenzelm@12897
  1791
wenzelm@12897
  1792
lemma Diff_mono: "A \<subseteq> C ==> D \<subseteq> B ==> A - B \<subseteq> C - D"
wenzelm@12897
  1793
  by blast
wenzelm@12897
  1794
wenzelm@12897
  1795
lemma Compl_anti_mono: "A \<subseteq> B ==> -B \<subseteq> -A"
wenzelm@12897
  1796
  by blast
wenzelm@12897
  1797
wenzelm@12897
  1798
text {* \medskip Monotonicity of implications. *}
wenzelm@12897
  1799
wenzelm@12897
  1800
lemma in_mono: "A \<subseteq> B ==> x \<in> A --> x \<in> B"
wenzelm@12897
  1801
  apply (rule impI)
wenzelm@12897
  1802
  apply (erule subsetD)
wenzelm@12897
  1803
  apply assumption
wenzelm@12897
  1804
  done
wenzelm@12897
  1805
wenzelm@12897
  1806
lemma conj_mono: "P1 --> Q1 ==> P2 --> Q2 ==> (P1 & P2) --> (Q1 & Q2)"
wenzelm@12897
  1807
  by rules
wenzelm@12897
  1808
wenzelm@12897
  1809
lemma disj_mono: "P1 --> Q1 ==> P2 --> Q2 ==> (P1 | P2) --> (Q1 | Q2)"
wenzelm@12897
  1810
  by rules
wenzelm@12897
  1811
wenzelm@12897
  1812
lemma imp_mono: "Q1 --> P1 ==> P2 --> Q2 ==> (P1 --> P2) --> (Q1 --> Q2)"
wenzelm@12897
  1813
  by rules
wenzelm@12897
  1814
wenzelm@12897
  1815
lemma imp_refl: "P --> P" ..
wenzelm@12897
  1816
wenzelm@12897
  1817
lemma ex_mono: "(!!x. P x --> Q x) ==> (EX x. P x) --> (EX x. Q x)"
wenzelm@12897
  1818
  by rules
wenzelm@12897
  1819
wenzelm@12897
  1820
lemma all_mono: "(!!x. P x --> Q x) ==> (ALL x. P x) --> (ALL x. Q x)"
wenzelm@12897
  1821
  by rules
wenzelm@12897
  1822
wenzelm@12897
  1823
lemma Collect_mono: "(!!x. P x --> Q x) ==> Collect P \<subseteq> Collect Q"
wenzelm@12897
  1824
  by blast
wenzelm@12897
  1825
wenzelm@12897
  1826
lemma Int_Collect_mono:
wenzelm@12897
  1827
    "A \<subseteq> B ==> (!!x. x \<in> A ==> P x --> Q x) ==> A \<inter> Collect P \<subseteq> B \<inter> Collect Q"
wenzelm@12897
  1828
  by blast
wenzelm@12897
  1829
wenzelm@12897
  1830
lemmas basic_monos =
wenzelm@12897
  1831
  subset_refl imp_refl disj_mono conj_mono
wenzelm@12897
  1832
  ex_mono Collect_mono in_mono
wenzelm@12897
  1833
wenzelm@12897
  1834
lemma eq_to_mono: "a = b ==> c = d ==> b --> d ==> a --> c"
wenzelm@12897
  1835
  by rules
wenzelm@12897
  1836
wenzelm@12897
  1837
lemma eq_to_mono2: "a = b ==> c = d ==> ~ b --> ~ d ==> ~ a --> ~ c"
wenzelm@12897
  1838
  by rules
wenzelm@11979
  1839
wenzelm@11982
  1840
lemma Least_mono:
wenzelm@11982
  1841
  "mono (f::'a::order => 'b::order) ==> EX x:S. ALL y:S. x <= y
wenzelm@11982
  1842
    ==> (LEAST y. y : f ` S) = f (LEAST x. x : S)"
wenzelm@11982
  1843
    -- {* Courtesy of Stephan Merz *}
wenzelm@11982
  1844
  apply clarify
wenzelm@11982
  1845
  apply (erule_tac P = "%x. x : S" in LeastI2)
wenzelm@11982
  1846
   apply fast
wenzelm@11982
  1847
  apply (rule LeastI2)
wenzelm@11982
  1848
  apply (auto elim: monoD intro!: order_antisym)
wenzelm@11982
  1849
  done
wenzelm@11982
  1850
wenzelm@12020
  1851
wenzelm@12257
  1852
subsection {* Inverse image of a function *}
wenzelm@12257
  1853
wenzelm@12257
  1854
constdefs
wenzelm@12257
  1855
  vimage :: "('a => 'b) => 'b set => 'a set"    (infixr "-`" 90)
wenzelm@12257
  1856
  "f -` B == {x. f x : B}"
wenzelm@12257
  1857
wenzelm@12257
  1858
wenzelm@12257
  1859
subsubsection {* Basic rules *}
wenzelm@12257
  1860
wenzelm@12257
  1861
lemma vimage_eq [simp]: "(a : f -` B) = (f a : B)"
wenzelm@12257
  1862
  by (unfold vimage_def) blast
wenzelm@12257
  1863
wenzelm@12257
  1864
lemma vimage_singleton_eq: "(a : f -` {b}) = (f a = b)"
wenzelm@12257
  1865
  by simp
wenzelm@12257
  1866
wenzelm@12257
  1867
lemma vimageI [intro]: "f a = b ==> b:B ==> a : f -` B"
wenzelm@12257
  1868
  by (unfold vimage_def) blast
wenzelm@12257
  1869
wenzelm@12257
  1870
lemma vimageI2: "f a : A ==> a : f -` A"
wenzelm@12257
  1871
  by (unfold vimage_def) fast
wenzelm@12257
  1872
wenzelm@12257
  1873
lemma vimageE [elim!]: "a: f -` B ==> (!!x. f a = x ==> x:B ==> P) ==> P"
wenzelm@12257
  1874
  by (unfold vimage_def) blast
wenzelm@12257
  1875
wenzelm@12257
  1876
lemma vimageD: "a : f -` A ==> f a : A"
wenzelm@12257
  1877
  by (unfold vimage_def) fast
wenzelm@12257
  1878
wenzelm@12257
  1879
wenzelm@12257
  1880
subsubsection {* Equations *}
wenzelm@12257
  1881
wenzelm@12257
  1882
lemma vimage_empty [simp]: "f -` {} = {}"
wenzelm@12257
  1883
  by blast
wenzelm@12257
  1884
wenzelm@12257
  1885
lemma vimage_Compl: "f -` (-A) = -(f -` A)"
wenzelm@12257
  1886
  by blast
wenzelm@12257
  1887
wenzelm@12257
  1888
lemma vimage_Un [simp]: "f -` (A Un B) = (f -` A) Un (f -` B)"
wenzelm@12257
  1889
  by blast
wenzelm@12257
  1890
wenzelm@12257
  1891
lemma vimage_Int [simp]: "f -` (A Int B) = (f -` A) Int (f -` B)"
wenzelm@12257
  1892
  by fast
wenzelm@12257
  1893
wenzelm@12257
  1894
lemma vimage_Union: "f -` (Union A) = (UN X:A. f -` X)"
wenzelm@12257
  1895
  by blast
wenzelm@12257
  1896
wenzelm@12257
  1897
lemma vimage_UN: "f-`(UN x:A. B x) = (UN x:A. f -` B x)"
wenzelm@12257
  1898
  by blast
wenzelm@12257
  1899
wenzelm@12257
  1900
lemma vimage_INT: "f-`(INT x:A. B x) = (INT x:A. f -` B x)"
wenzelm@12257
  1901
  by blast
wenzelm@12257
  1902
wenzelm@12257
  1903
lemma vimage_Collect_eq [simp]: "f -` Collect P = {y. P (f y)}"
wenzelm@12257
  1904
  by blast
wenzelm@12257
  1905
wenzelm@12257
  1906
lemma vimage_Collect: "(!!x. P (f x) = Q x) ==> f -` (Collect P) = Collect Q"
wenzelm@12257
  1907
  by blast
wenzelm@12257
  1908
wenzelm@12257
  1909
lemma vimage_insert: "f-`(insert a B) = (f-`{a}) Un (f-`B)"
wenzelm@12257
  1910
  -- {* NOT suitable for rewriting because of the recurrence of @{term "{a}"}. *}
wenzelm@12257
  1911
  by blast
wenzelm@12257
  1912
wenzelm@12257
  1913
lemma vimage_Diff: "f -` (A - B) = (f -` A) - (f -` B)"
wenzelm@12257
  1914
  by blast
wenzelm@12257
  1915
wenzelm@12257
  1916
lemma vimage_UNIV [simp]: "f -` UNIV = UNIV"
wenzelm@12257
  1917
  by blast
wenzelm@12257
  1918
wenzelm@12257
  1919
lemma vimage_eq_UN: "f-`B = (UN y: B. f-`{y})"
wenzelm@12257
  1920
  -- {* NOT suitable for rewriting *}
wenzelm@12257
  1921
  by blast
wenzelm@12257
  1922
wenzelm@12897
  1923
lemma vimage_mono: "A \<subseteq> B ==> f -` A \<subseteq> f -` B"
wenzelm@12257
  1924
  -- {* monotonicity *}
wenzelm@12257
  1925
  by blast
wenzelm@12257
  1926
wenzelm@12257
  1927
wenzelm@12023
  1928
subsection {* Transitivity rules for calculational reasoning *}
wenzelm@12020
  1929
wenzelm@12020
  1930
lemma forw_subst: "a = b ==> P b ==> P a"
wenzelm@12020
  1931
  by (rule ssubst)
wenzelm@12020
  1932
wenzelm@12020
  1933
lemma back_subst: "P a ==> a = b ==> P b"
wenzelm@12020
  1934
  by (rule subst)
wenzelm@12020
  1935
wenzelm@12897
  1936
lemma set_rev_mp: "x:A ==> A \<subseteq> B ==> x:B"
wenzelm@12020
  1937
  by (rule subsetD)
wenzelm@12020
  1938
wenzelm@12897
  1939
lemma set_mp: "A \<subseteq> B ==> x:A ==> x:B"
wenzelm@12020
  1940
  by (rule subsetD)
wenzelm@12020
  1941
wenzelm@12020
  1942
lemma order_neq_le_trans: "a ~= b ==> (a::'a::order) <= b ==> a < b"
wenzelm@12020
  1943
  by (simp add: order_less_le)
wenzelm@12020
  1944
wenzelm@12020
  1945
lemma order_le_neq_trans: "(a::'a::order) <= b ==> a ~= b ==> a < b"
wenzelm@12020
  1946
  by (simp add: order_less_le)
wenzelm@12020
  1947
wenzelm@12020
  1948
lemma order_less_asym': "(a::'a::order) < b ==> b < a ==> P"
wenzelm@12020
  1949
  by (rule order_less_asym)
wenzelm@12020
  1950
wenzelm@12020
  1951
lemma ord_le_eq_trans: "a <= b ==> b = c ==> a <= c"
wenzelm@12020
  1952
  by (rule subst)
wenzelm@12020
  1953
wenzelm@12020
  1954
lemma ord_eq_le_trans: "a = b ==> b <= c ==> a <= c"
wenzelm@12020
  1955
  by (rule ssubst)
wenzelm@12020
  1956
wenzelm@12020
  1957
lemma ord_less_eq_trans: "a < b ==> b = c ==> a < c"
wenzelm@12020
  1958
  by (rule subst)
wenzelm@12020
  1959
wenzelm@12020
  1960
lemma ord_eq_less_trans: "a = b ==> b < c ==> a < c"
wenzelm@12020
  1961
  by (rule ssubst)
wenzelm@12020
  1962
wenzelm@12020
  1963
lemma order_less_subst2: "(a::'a::order) < b ==> f b < (c::'c::order) ==>
wenzelm@12020
  1964
  (!!x y. x < y ==> f x < f y) ==> f a < c"
wenzelm@12020
  1965
proof -
wenzelm@12020
  1966
  assume r: "!!x y. x < y ==> f x < f y"
wenzelm@12020
  1967
  assume "a < b" hence "f a < f b" by (rule r)
wenzelm@12020
  1968
  also assume "f b < c"
wenzelm@12020
  1969
  finally (order_less_trans) show ?thesis .
wenzelm@12020
  1970
qed
wenzelm@12020
  1971
wenzelm@12020
  1972
lemma order_less_subst1: "(a::'a::order) < f b ==> (b::'b::order) < c ==>
wenzelm@12020
  1973
  (!!x y. x < y ==> f x < f y) ==> a < f c"
wenzelm@12020
  1974
proof -
wenzelm@12020
  1975
  assume r: "!!x y. x < y ==> f x < f y"
wenzelm@12020
  1976
  assume "a < f b"
wenzelm@12020
  1977
  also assume "b < c" hence "f b < f c" by (rule r)
wenzelm@12020
  1978
  finally (order_less_trans) show ?thesis .
wenzelm@12020
  1979
qed
wenzelm@12020
  1980
wenzelm@12020
  1981
lemma order_le_less_subst2: "(a::'a::order) <= b ==> f b < (c::'c::order) ==>
wenzelm@12020
  1982
  (!!x y. x <= y ==> f x <= f y) ==> f a < c"
wenzelm@12020
  1983
proof -
wenzelm@12020
  1984
  assume r: "!!x y. x <= y ==> f x <= f y"
wenzelm@12020
  1985
  assume "a <= b" hence "f a <= f b" by (rule r)
wenzelm@12020
  1986
  also assume "f b < c"
wenzelm@12020
  1987
  finally (order_le_less_trans) show ?thesis .
wenzelm@12020
  1988
qed
wenzelm@12020
  1989
wenzelm@12020
  1990
lemma order_le_less_subst1: "(a::'a::order) <= f b ==> (b::'b::order) < c ==>
wenzelm@12020
  1991
  (!!x y. x < y ==> f x < f y) ==> a < f c"
wenzelm@12020
  1992
proof -
wenzelm@12020
  1993
  assume r: "!!x y. x < y ==> f x < f y"
wenzelm@12020
  1994
  assume "a <= f b"
wenzelm@12020
  1995
  also assume "b < c" hence "f b < f c" by (rule r)
wenzelm@12020
  1996
  finally (order_le_less_trans) show ?thesis .
wenzelm@12020
  1997
qed
wenzelm@12020
  1998
wenzelm@12020
  1999
lemma order_less_le_subst2: "(a::'a::order) < b ==> f b <= (c::'c::order) ==>
wenzelm@12020
  2000
  (!!x y. x < y ==> f x < f y) ==> f a < c"
wenzelm@12020
  2001
proof -
wenzelm@12020
  2002
  assume r: "!!x y. x < y ==> f x < f y"
wenzelm@12020
  2003
  assume "a < b" hence "f a < f b" by (rule r)
wenzelm@12020
  2004
  also assume "f b <= c"
wenzelm@12020
  2005
  finally (order_less_le_trans) show ?thesis .
wenzelm@12020
  2006
qed
wenzelm@12020
  2007
wenzelm@12020
  2008
lemma order_less_le_subst1: "(a::'a::order) < f b ==> (b::'b::order) <= c ==>
wenzelm@12020
  2009
  (!!x y. x <= y ==> f x <= f y) ==> a < f c"
wenzelm@12020
  2010
proof -
wenzelm@12020
  2011
  assume r: "!!x y. x <= y ==> f x <= f y"
wenzelm@12020
  2012
  assume "a < f b"
wenzelm@12020
  2013
  also assume "b <= c" hence "f b <= f c" by (rule r)
wenzelm@12020
  2014
  finally (order_less_le_trans) show ?thesis .
wenzelm@12020
  2015
qed
wenzelm@12020
  2016
wenzelm@12020
  2017
lemma order_subst1: "(a::'a::order) <= f b ==> (b::'b::order) <= c ==>
wenzelm@12020
  2018
  (!!x y. x <= y ==> f x <= f y) ==> a <= f c"
wenzelm@12020
  2019
proof -
wenzelm@12020
  2020
  assume r: "!!x y. x <= y ==> f x <= f y"
wenzelm@12020
  2021
  assume "a <= f b"
wenzelm@12020
  2022
  also assume "b <= c" hence "f b <= f c" by (rule r)
wenzelm@12020
  2023
  finally (order_trans) show ?thesis .
wenzelm@12020
  2024
qed
wenzelm@12020
  2025
wenzelm@12020
  2026
lemma order_subst2: "(a::'a::order) <= b ==> f b <= (c::'c::order) ==>
wenzelm@12020
  2027
  (!!x y. x <= y ==> f x <= f y) ==> f a <= c"
wenzelm@12020
  2028
proof -
wenzelm@12020
  2029
  assume r: "!!x y. x <= y ==> f x <= f y"
wenzelm@12020
  2030
  assume "a <= b" hence "f a <= f b" by (rule r)
wenzelm@12020
  2031
  also assume "f b <= c"
wenzelm@12020
  2032
  finally (order_trans) show ?thesis .
wenzelm@12020
  2033
qed
wenzelm@12020
  2034
wenzelm@12020
  2035
lemma ord_le_eq_subst: "a <= b ==> f b = c ==>
wenzelm@12020
  2036
  (!!x y. x <= y ==> f x <= f y) ==> f a <= c"
wenzelm@12020
  2037
proof -
wenzelm@12020
  2038
  assume r: "!!x y. x <= y ==> f x <= f y"
wenzelm@12020
  2039
  assume "a <= b" hence "f a <= f b" by (rule r)
wenzelm@12020
  2040
  also assume "f b = c"
wenzelm@12020
  2041
  finally (ord_le_eq_trans) show ?thesis .
wenzelm@12020
  2042
qed
wenzelm@12020
  2043
wenzelm@12020
  2044
lemma ord_eq_le_subst: "a = f b ==> b <= c ==>
wenzelm@12020
  2045
  (!!x y. x <= y ==> f x <= f y) ==> a <= f c"
wenzelm@12020
  2046
proof -
wenzelm@12020
  2047
  assume r: "!!x y. x <= y ==> f x <= f y"
wenzelm@12020
  2048
  assume "a = f b"
wenzelm@12020
  2049
  also assume "b <= c" hence "f b <= f c" by (rule r)
wenzelm@12020
  2050
  finally (ord_eq_le_trans) show ?thesis .
wenzelm@12020
  2051
qed
wenzelm@12020
  2052
wenzelm@12020
  2053
lemma ord_less_eq_subst: "a < b ==> f b = c ==>
wenzelm@12020
  2054
  (!!x y. x < y ==> f x < f y) ==> f a < c"
wenzelm@12020
  2055
proof -
wenzelm@12020
  2056
  assume r: "!!x y. x < y ==> f x < f y"
wenzelm@12020
  2057
  assume "a < b" hence "f a < f b" by (rule r)
wenzelm@12020
  2058
  also assume "f b = c"
wenzelm@12020
  2059
  finally (ord_less_eq_trans) show ?thesis .
wenzelm@12020
  2060
qed
wenzelm@12020
  2061
wenzelm@12020
  2062
lemma ord_eq_less_subst: "a = f b ==> b < c ==>
wenzelm@12020
  2063
  (!!x y. x < y ==> f x < f y) ==> a < f c"
wenzelm@12020
  2064
proof -
wenzelm@12020
  2065
  assume r: "!!x y. x < y ==> f x < f y"
wenzelm@12020
  2066
  assume "a = f b"
wenzelm@12020
  2067
  also assume "b < c" hence "f b < f c" by (rule r)
wenzelm@12020
  2068
  finally (ord_eq_less_trans) show ?thesis .
wenzelm@12020
  2069
qed
wenzelm@12020
  2070
wenzelm@12020
  2071
text {*
wenzelm@12020
  2072
  Note that this list of rules is in reverse order of priorities.
wenzelm@12020
  2073
*}
wenzelm@12020
  2074
wenzelm@12020
  2075
lemmas basic_trans_rules [trans] =
wenzelm@12020
  2076
  order_less_subst2
wenzelm@12020
  2077
  order_less_subst1
wenzelm@12020
  2078
  order_le_less_subst2
wenzelm@12020
  2079
  order_le_less_subst1
wenzelm@12020
  2080
  order_less_le_subst2
wenzelm@12020
  2081
  order_less_le_subst1
wenzelm@12020
  2082
  order_subst2
wenzelm@12020
  2083
  order_subst1
wenzelm@12020
  2084
  ord_le_eq_subst
wenzelm@12020
  2085
  ord_eq_le_subst
wenzelm@12020
  2086
  ord_less_eq_subst
wenzelm@12020
  2087
  ord_eq_less_subst
wenzelm@12020
  2088
  forw_subst
wenzelm@12020
  2089
  back_subst
wenzelm@12020
  2090
  rev_mp
wenzelm@12020
  2091
  mp
wenzelm@12020
  2092
  set_rev_mp
wenzelm@12020
  2093
  set_mp
wenzelm@12020
  2094
  order_neq_le_trans
wenzelm@12020
  2095
  order_le_neq_trans
wenzelm@12020
  2096
  order_less_trans
wenzelm@12020
  2097
  order_less_asym'
wenzelm@12020
  2098
  order_le_less_trans
wenzelm@12020
  2099
  order_less_le_trans
wenzelm@12020
  2100
  order_trans
wenzelm@12020
  2101
  order_antisym
wenzelm@12020
  2102
  ord_le_eq_trans
wenzelm@12020
  2103
  ord_eq_le_trans
wenzelm@12020
  2104
  ord_less_eq_trans
wenzelm@12020
  2105
  ord_eq_less_trans
wenzelm@12020
  2106
  trans
wenzelm@12020
  2107
wenzelm@11979
  2108
end