doc-src/Logics/ZF-rules.txt
changeset 104 d8205bb279a7
equal deleted inserted replaced
103:30bd42401ab2 104:d8205bb279a7
       
     1 %%%% RULES.ML
       
     2 
       
     3 \idx{empty_set}    ~(x:0)
       
     4 \idx{union_iff}    A:Union(C) <-> (EX B:C. A:B)
       
     5 \idx{power_set}    A : Pow(B) <-> A <= B
       
     6 \idx{infinity}     0:Inf & (ALL y:Inf. succ(y): Inf)
       
     7 \idx{foundation}   A=0 | (EX x:A. ALL y:x. ~ y:A)
       
     8 
       
     9 \idx{replacement}  (!!x y z.[| x:A; P(x,y); P(x,z) |] ==> y=z) ==>
       
    10                    y : PrimReplace(A,P) <-> (EX x:A. P(x,y))
       
    11 
       
    12 \idx{Replace_def}  Replace(A,P) == PrimReplace(A, %x y. (EX!z.P(x,z)) & P(x,y))
       
    13 \idx{RepFun_def}   RepFun(A,f) == Replace(A, %x u. u=f(x))
       
    14 \idx{Collect_def}  Collect(A,P) == \{ y . x:A, x=y & P(x)\}
       
    15 \idx{the_def}      The(P) == Union(\{y . x:\{0\}, P(y)\})
       
    16 
       
    17 \idx{Upair_def}    Upair(a,b) == 
       
    18                    \{y. x:Pow(Pow(0)), (x=0 & y=a) | (x=Pow(0) & y=b)\}
       
    19 
       
    20 \idx{Inter_def}    Inter(A) == \{ x:Union(A) . ALL y:A. x:y\}
       
    21 
       
    22 \idx{Un_def}       A Un  B  == Union(Upair(A,B))
       
    23 \idx{Int_def}      A Int B  == Inter(Upair(A,B))
       
    24 \idx{Diff_def}     A - B    == \{ x:A . ~(x:B) \}
       
    25 \idx{cons_def}     cons(a,A) == Upair(a,a) Un A
       
    26 \idx{succ_def}     succ(i) == cons(i,i)
       
    27 
       
    28 \idx{Pair_def}     <a,b>  == \{\{a,a\}, \{a,b\}\}
       
    29 \idx{fst_def}      fst(A) == THE x. EX y. A=<x,y>
       
    30 \idx{snd_def}      snd(A) == THE y. EX x. A=<x,y>
       
    31 \idx{split_def}    split(p,c) == THE y. EX a b. p=<a,b> & y=c(a,b)
       
    32 \idx{Sigma_def}    Sigma(A,B) == UN x:A. UN y:B(x). \{<x,y>\}
       
    33 
       
    34 \idx{domain_def}   domain(r) == \{a:Union(Union(r)) . EX b. <a,b> : r\}
       
    35 \idx{range_def}    range(r) == \{b:Union(Union(r)) . EX a. <a,b> : r\}
       
    36 \idx{field_def}    field(r) == domain(r) Un range(r)
       
    37 \idx{image_def}    r``A == \{y : range(r) . EX x:A. <x,y> : r\}
       
    38 \idx{vimage_def}   r -`` A == \{x : domain(r) . EX y:A. <x,y> : r\}
       
    39 
       
    40 \idx{lam_def}      Lambda(A,f) == RepFun(A, %x. <x,f(x)>)
       
    41 \idx{apply_def}    f`a == THE y. <a,y> : f
       
    42 \idx{restrict_def} restrict(f,A) == lam x:A.f`x
       
    43 \idx{Pi_def}       Pi(A,B)  == \{f: Pow(Sigma(A,B)). ALL x:A. EX! y. <x,y>: f\}
       
    44 
       
    45 \idx{subset_def}         A <= B == ALL x:A. x:B
       
    46 \idx{strict_subset_def}  A <! B   == A <=B & ~(A=B)
       
    47 \idx{extension}          A = B <-> A <= B & B <= A
       
    48 
       
    49 \idx{Ball_def}   Ball(A,P) == ALL x. x:A --> P(x)
       
    50 \idx{Bex_def}    Bex(A,P) == EX x. x:A & P(x)
       
    51 
       
    52 
       
    53 %%%% LEMMAS.ML
       
    54 
       
    55 \idx{ballI}       [| !!x. x:A ==> P(x) |] ==> ALL x:A. P(x)
       
    56 \idx{bspec}       [| ALL x:A. P(x);  x: A |] ==> P(x)
       
    57 \idx{ballE}       [| ALL x:A. P(x);  P(x) ==> Q;  ~ x:A ==> Q |] ==> Q
       
    58 
       
    59 \idx{ball_cong}   [| A=A';  !!x. x:A' ==> P(x) <-> P'(x) |] ==> 
       
    60             (ALL x:A. P(x)) <-> (ALL x:A'. P'(x))
       
    61 
       
    62 \idx{bexI}        [| P(x);  x: A |] ==> EX x:A. P(x)
       
    63 \idx{bexCI}       [| ALL x:A. ~P(x) ==> P(a);  a: A |] ==> EX x:A.P(x)
       
    64 \idx{bexE}        [| EX x:A. P(x);  !!x. [| x:A; P(x) |] ==> Q |] ==> Q
       
    65 
       
    66 \idx{bex_cong}    [| A=A';  !!x. x:A' ==> P(x) <-> P'(x) |] ==> 
       
    67             (EX x:A. P(x)) <-> (EX x:A'. P'(x))
       
    68 
       
    69 \idx{subsetI}       (!!x.x:A ==> x:B) ==> A <= B
       
    70 \idx{subsetD}       [| A <= B;  c:A |] ==> c:B
       
    71 \idx{subsetCE}      [| A <= B;  ~(c:A) ==> P;  c:B ==> P |] ==> P
       
    72 \idx{subset_refl}   A <= A
       
    73 \idx{subset_trans}  [| A<=B;  B<=C |] ==> A<=C
       
    74 
       
    75 \idx{equalityI}     [| A <= B;  B <= A |] ==> A = B
       
    76 \idx{equalityD1}    A = B ==> A<=B
       
    77 \idx{equalityD2}    A = B ==> B<=A
       
    78 \idx{equalityE}     [| A = B;  [| A<=B; B<=A |] ==> P |]  ==>  P
       
    79 
       
    80 \idx{emptyE}          a:0 ==> P
       
    81 \idx{empty_subsetI}   0 <= A
       
    82 \idx{equals0I}        [| !!y. y:A ==> False |] ==> A=0
       
    83 \idx{equals0D}        [| A=0;  a:A |] ==> P
       
    84 
       
    85 \idx{PowI}            A <= B ==> A : Pow(B)
       
    86 \idx{PowD}            A : Pow(B)  ==>  A<=B
       
    87 
       
    88 \idx{ReplaceI}      [| x: A;  P(x,b);  !!y. P(x,y) ==> y=b |] ==> 
       
    89               b : \{y. x:A, P(x,y)\}
       
    90 
       
    91 \idx{ReplaceE}      [| b : \{y. x:A, P(x,y)\};  
       
    92                  !!x. [| x: A;  P(x,b);  ALL y. P(x,y)-->y=b |] ==> R 
       
    93               |] ==> R
       
    94 
       
    95 \idx{Replace_cong}  [| A=B;  !!x y. x:B ==> P(x,y) <-> Q(x,y) |] ==> 
       
    96               \{y. x:A, P(x,y)\} = \{y. x:B, Q(x,y)\}
       
    97 
       
    98 \idx{RepFunI}       [| a : A |] ==> f(a) : RepFun(A,f)
       
    99 \idx{RepFunE}       [| b : RepFun(A, %x.f(x));  
       
   100                  !!x.[| x:A;  b=f(x) |] ==> P |] ==> P
       
   101 
       
   102 \idx{RepFun_cong}   [| A=B;  !!x. x:B ==> f(x)=g(x) |] ==> 
       
   103               RepFun(A, %x.f(x)) = RepFun(B, %x.g(x))
       
   104 
       
   105 
       
   106 \idx{separation}     x : Collect(A,P) <-> x:A & P(x)
       
   107 \idx{CollectI}       [| a:A;  P(a) |] ==> a : \{x:A. P(x)\}
       
   108 \idx{CollectE}       [| a : \{x:A. P(x)\};  [| a:A; P(a) |] ==> R |] ==> R
       
   109 \idx{CollectD1}      a : \{x:A. P(x)\} ==> a:A
       
   110 \idx{CollectD2}      a : \{x:A. P(x)\} ==> P(a)
       
   111 
       
   112 \idx{Collect_cong}   [| A=B;  !!x. x:B ==> P(x) <-> Q(x) |] ==> 
       
   113                \{x:A. P(x)\} = \{x:B. Q(x)\}
       
   114 
       
   115 \idx{UnionI}    [| B: C;  A: B |] ==> A: Union(C)
       
   116 \idx{UnionE}    [| A : Union(C);  !!B.[| A: B;  B: C |] ==> R |] ==> R
       
   117 
       
   118 \idx{InterI}    [| !!x. x: C ==> A: x;  c:C |] ==> A : Inter(C)
       
   119 \idx{InterD}    [| A : Inter(C);  B : C |] ==> A : B
       
   120 \idx{InterE}    [| A : Inter(C);  A:B ==> R;  ~ B:C ==> R |] ==> R
       
   121 
       
   122 \idx{UN_I}      [| a: A;  b: B(a) |] ==> b: (UN x:A. B(x))
       
   123 \idx{UN_E}      [| b : (UN x:A. B(x));  !!x.[| x: A;  b: B(x) |] ==> R |] ==> R
       
   124 
       
   125 \idx{INT_I}     [| !!x. x: A ==> b: B(x);  a: A |] ==> b: (INT x:A. B(x))
       
   126 \idx{INT_E}     [| b : (INT x:A. B(x));  a: A |] ==> b : B(a)
       
   127 
       
   128 
       
   129 %%%% UPAIR.ML
       
   130 
       
   131 \idx{pairing}      a:Upair(b,c) <-> (a=b | a=c)
       
   132 \idx{UpairI1}      a : Upair(a,b)
       
   133 \idx{UpairI2}      b : Upair(a,b)
       
   134 \idx{UpairE}       [| a : Upair(b,c);  a = b ==> P;  a = c ==> P |] ==> P
       
   135 
       
   136 \idx{UnI1}         c : A ==> c : A Un B
       
   137 \idx{UnI2}         c : B ==> c : A Un B
       
   138 \idx{UnCI}         (~c : B ==> c : A) ==> c : A Un B
       
   139 \idx{UnE}          [| c : A Un B;  c:A ==> P;  c:B ==> P |] ==> P
       
   140 
       
   141 \idx{IntI}         [| c : A;  c : B |] ==> c : A Int B
       
   142 \idx{IntD1}        c : A Int B ==> c : A
       
   143 \idx{IntD2}        c : A Int B ==> c : B
       
   144 \idx{IntE}         [| c : A Int B;  [| c:A; c:B |] ==> P |] ==> P
       
   145 
       
   146 \idx{DiffI}        [| c : A;  ~ c : B |] ==> c : A - B
       
   147 \idx{DiffD1}       c : A - B ==> c : A
       
   148 \idx{DiffD2}       [| c : A - B;  c : B |] ==> P
       
   149 \idx{DiffE}        [| c : A - B;  [| c:A; ~ c:B |] ==> P |] ==> P
       
   150 
       
   151 \idx{consI1}       a : cons(a,B)
       
   152 \idx{consI2}       a : B ==> a : cons(b,B)
       
   153 \idx{consCI}       (~ a:B ==> a=b) ==> a: cons(b,B)
       
   154 \idx{consE}        [| a : cons(b,A);  a=b ==> P;  a:A ==> P |] ==> P
       
   155 
       
   156 \idx{singletonI}   a : \{a\}
       
   157 \idx{singletonE}   [| a : \{b\}; a=b ==> P |] ==> P
       
   158 
       
   159 \idx{succI1}       i : succ(i)
       
   160 \idx{succI2}       i : j ==> i : succ(j)
       
   161 \idx{succCI}       (~ i:j ==> i=j) ==> i: succ(j)
       
   162 \idx{succE}        [| i : succ(j);  i=j ==> P;  i:j ==> P |] ==> P
       
   163 \idx{succ_neq_0}   [| succ(n)=0 |] ==> P
       
   164 \idx{succ_inject}  succ(m) = succ(n) ==> m=n
       
   165 
       
   166 \idx{the_equality}     [| P(a);  !!x. P(x) ==> x=a |] ==> (THE x. P(x)) = a
       
   167 \idx{theI}             EX! x. P(x) ==> P(THE x. P(x))
       
   168 
       
   169 \idx{mem_anti_sym}     [| a:b;  b:a |] ==> P
       
   170 \idx{mem_anti_refl}    a:a ==> P
       
   171 
       
   172 
       
   173 %%% SUBSET.ML
       
   174 
       
   175 \idx{Union_upper}       B:A ==> B <= Union(A)
       
   176 \idx{Union_least}       [| !!x. x:A ==> x<=C |] ==> Union(A) <= C
       
   177 
       
   178 \idx{Inter_lower}       B:A ==> Inter(A) <= B
       
   179 \idx{Inter_greatest}    [| a:A;  !!x. x:A ==> C<=x |] ==> C <= Inter(A)
       
   180 
       
   181 \idx{Un_upper1}         A <= A Un B
       
   182 \idx{Un_upper2}         B <= A Un B
       
   183 \idx{Un_least}          [| A<=C;  B<=C |] ==> A Un B <= C
       
   184 
       
   185 \idx{Int_lower1}        A Int B <= A
       
   186 \idx{Int_lower2}        A Int B <= B
       
   187 \idx{Int_greatest}      [| C<=A;  C<=B |] ==> C <= A Int B
       
   188 
       
   189 \idx{Diff_subset}       A-B <= A
       
   190 \idx{Diff_contains}     [| C<=A;  C Int B = 0 |] ==> C <= A-B
       
   191 
       
   192 \idx{Collect_subset}    Collect(A,P) <= A
       
   193 
       
   194 %%% PAIR.ML
       
   195 
       
   196 \idx{Pair_inject1}    <a,b> = <c,d> ==> a=c
       
   197 \idx{Pair_inject2}    <a,b> = <c,d> ==> b=d
       
   198 \idx{Pair_inject}     [| <a,b> = <c,d>;  [| a=c; b=d |] ==> P |] ==> P
       
   199 \idx{Pair_neq_0}      <a,b>=0 ==> P
       
   200 
       
   201 \idx{fst_conv}        fst(<a,b>) = a
       
   202 \idx{snd_conv}        snd(<a,b>) = b
       
   203 \idx{split_conv}      split(<a,b>, %x y.c(x,y)) = c(a,b)
       
   204 
       
   205 \idx{SigmaI}    [| a:A;  b:B(a) |] ==> <a,b> : (SUM x:A. B(x))
       
   206 
       
   207 \idx{SigmaE}    [| c: (SUM x:A. B(x));  
       
   208              !!x y.[| x:A;  y:B(x);  c=<x,y> |] ==> P 
       
   209           |] ==> P
       
   210 
       
   211 \idx{SigmaE2}   [| <a,b> : (SUM x:A. B(x));    
       
   212              [| a:A;  b:B(a) |] ==> P   
       
   213           |] ==> P
       
   214 
       
   215 
       
   216 %%% DOMRANGE.ML
       
   217 
       
   218 \idx{domainI}        <a,b>: r ==> a : domain(r)
       
   219 \idx{domainE}        [| a : domain(r);  !!y. <a,y>: r ==> P |] ==> P
       
   220 \idx{domain_subset}  domain(Sigma(A,B)) <= A
       
   221 
       
   222 \idx{rangeI}         <a,b>: r ==> b : range(r)
       
   223 \idx{rangeE}         [| b : range(r);  !!x. <x,b>: r ==> P |] ==> P
       
   224 \idx{range_subset}   range(A*B) <= B
       
   225 
       
   226 \idx{fieldI1}        <a,b>: r ==> a : field(r)
       
   227 \idx{fieldI2}        <a,b>: r ==> b : field(r)
       
   228 \idx{fieldCI}        (~ <c,a>:r ==> <a,b>: r) ==> a : field(r)
       
   229 
       
   230 \idx{fieldE}         [| a : field(r);  
       
   231                   !!x. <a,x>: r ==> P;  
       
   232                   !!x. <x,a>: r ==> P      
       
   233                |] ==> P
       
   234 
       
   235 \idx{field_subset}   field(A*A) <= A
       
   236 
       
   237 \idx{imageI}         [| <a,b>: r;  a:A |] ==> b : r``A
       
   238 \idx{imageE}         [| b: r``A;  !!x.[| <x,b>: r;  x:A |] ==> P |] ==> P
       
   239 
       
   240 \idx{vimageI}        [| <a,b>: r;  b:B |] ==> a : r-``B
       
   241 \idx{vimageE}        [| a: r-``B;  !!x.[| <a,x>: r;  x:B |] ==> P |] ==> P
       
   242 
       
   243 
       
   244 %%% FUNC.ML
       
   245 
       
   246 \idx{fun_is_rel}       f: (PROD x:A.B(x)) ==> f <= Sigma(A,B)
       
   247 
       
   248 \idx{apply_equality}   [| <a,b>: f;  f: (PROD x:A.B(x)) |] ==> f`a = b
       
   249 \idx{apply_equality2}  [| <a,b>: f;  <a,c>: f;  f: (PROD x:A.B(x)) |] ==> b=c
       
   250 
       
   251 \idx{apply_type}       [| f: (PROD x:A.B(x));  a:A |] ==> f`a : B(a)
       
   252 \idx{apply_Pair}       [| f: (PROD x:A.B(x));  a:A |] ==> <a,f`a>: f
       
   253 \idx{apply_iff}        [| f: (PROD x:A.B(x));  a:A |] ==> <a,b>: f <-> f`a = b
       
   254 
       
   255 \idx{domain_type}      [| <a,b> : f;  f: (PROD x:A.B(x)) |] ==> a : A
       
   256 \idx{range_type}       [| <a,b> : f;  f: (PROD x:A.B(x)) |] ==> b : B(a)
       
   257 
       
   258 \idx{Pi_type}          [| f: A->C;  !!x. x:A ==> f`x : B(x) |] ==> f: Pi(A,B)
       
   259 \idx{domain_of_fun}    f : Pi(A,B) ==> domain(f)=A
       
   260 \idx{range_of_fun}     f : Pi(A,B) ==> f: A->range(f)
       
   261 
       
   262 \idx{fun_extension}    [| f : (PROD x:A.B(x));  g: (PROD x:A.D(x));  
       
   263                     !!x. x:A ==> f`x = g`x       
       
   264                  |] ==> f=g
       
   265 
       
   266 \idx{lamI}             a:A ==> <a,b(a)> : (lam x:A. b(x))
       
   267 \idx{lamE}             [| p: (lam x:A. b(x));  !!x.[| x:A; p=<x,b(x)> |] ==> P 
       
   268                  |] ==>  P
       
   269 
       
   270 \idx{lam_type}         [| !!x. x:A ==> b(x): B(x) |] ==> 
       
   271                  (lam x:A.b(x)) : (PROD x:A.B(x))
       
   272 
       
   273 \idx{beta_conv}        a : A ==> (lam x:A.b(x)) ` a = b(a)
       
   274 \idx{eta_conv}         f : (PROD x:A.B(x)) ==> (lam x:A. f`x) = f
       
   275 
       
   276 \idx{lam_theI}         (!!x. x:A ==> EX! y. Q(x,y)) ==> EX h. ALL x:A. Q(x, h`x)
       
   277 
       
   278 \idx{restrict_conv}          a : A ==> restrict(f,A) ` a = f`a
       
   279 \idx{restrict_type}          [| !!x. x:A ==> f`x: B(x) |] ==> 
       
   280                        restrict(f,A) : (PROD x:A.B(x))
       
   281 
       
   282 \idx{fun_empty}              0: 0->0
       
   283 \idx{fun_single}             \{<a,b>\} : \{a\} -> \{b\}
       
   284 
       
   285 \idx{fun_disjoint_Un}        [| f: A->B;  g: C->D;  A Int C = 0  |] ==>  
       
   286                        (f Un g) : (A Un C) -> (B Un D)
       
   287 
       
   288 \idx{fun_disjoint_apply1}    [| a:A;  f: A->B;  g: C->D;  A Int C = 0 |] ==>  
       
   289                        (f Un g)`a = f`a
       
   290 
       
   291 \idx{fun_disjoint_apply2}    [| c:C;  f: A->B;  g: C->D;  A Int C = 0 |] ==>  
       
   292                        (f Un g)`c = g`c
       
   293 
       
   294 
       
   295 %%% SIMPDATA.ML
       
   296 
       
   297   a\in a 		& \bimp &  False\\
       
   298   a\in \emptyset 	& \bimp &  False\\
       
   299   a \in A \union B 	& \bimp &  a\in A \disj a\in B\\
       
   300   a \in A \inter B 	& \bimp &  a\in A \conj a\in B\\
       
   301   a \in A-B 		& \bimp &  a\in A \conj \neg (a\in B)\\
       
   302   a \in {\tt cons}(b,B) & \bimp &  a=b \disj a\in B\\
       
   303   i \in {\tt succ}(j) 	& \bimp &  i=j \disj i\in j\\
       
   304   A\in \bigcup(C) 	& \bimp &  (\exists B. B\in C \conj A\in B)\\
       
   305   A\in \bigcap(C) 	& \bimp &  (\forall B. B\in C \imp A\in B)
       
   306 	\qquad (\exists B. B\in C)\\
       
   307   a \in {\tt Collect}(A,P) 	& \bimp &  a\in A \conj P(a)\\
       
   308   b \in {\tt RepFun}(A,f) 	& \bimp &  (\exists x. x\in A \conj b=f(x))
       
   309 
       
   310 equalities.ML perm.ML plus.ML nat.ML
       
   311 ----------------------------------------------------------------
       
   312 equalities.ML
       
   313 
       
   314 \idx{Int_absorb}         A Int A = A
       
   315 \idx{Int_commute}        A Int B = B Int A
       
   316 \idx{Int_assoc}          (A Int B) Int C  =  A Int (B Int C)
       
   317 \idx{Int_Un_distrib}     (A Un B) Int C  =  (A Int C) Un (B Int C)
       
   318 
       
   319 \idx{Un_absorb}          A Un A = A
       
   320 \idx{Un_commute}         A Un B = B Un A
       
   321 \idx{Un_assoc}           (A Un B) Un C  =  A Un (B Un C)
       
   322 \idx{Un_Int_distrib}     (A Int B) Un C  =  (A Un C) Int (B Un C)
       
   323 
       
   324 \idx{Diff_cancel}        A-A = 0
       
   325 \idx{Diff_disjoint}      A Int (B-A) = 0
       
   326 \idx{Diff_partition}     A<=B ==> A Un (B-A) = B
       
   327 \idx{double_complement}  [| A<=B; B<= C |] ==> (B - (C-A)) = A
       
   328 \idx{Diff_Un}            A - (B Un C) = (A-B) Int (A-C)
       
   329 \idx{Diff_Int}           A - (B Int C) = (A-B) Un (A-C)
       
   330 
       
   331 \idx{Union_Un_distrib}   Union(A Un B) = Union(A) Un Union(B)
       
   332 \idx{Inter_Un_distrib}   [| a:A;  b:B |] ==> 
       
   333                    Inter(A Un B) = Inter(A) Int Inter(B)
       
   334 
       
   335 \idx{Int_Union_RepFun}   A Int Union(B) = (UN C:B. A Int C)
       
   336 
       
   337 \idx{Un_Inter_RepFun}    b:B ==> 
       
   338                    A Un Inter(B) = (INT C:B. A Un C)
       
   339 
       
   340 \idx{SUM_Un_distrib1}    (SUM x:A Un B. C(x)) = 
       
   341                    (SUM x:A. C(x)) Un (SUM x:B. C(x))
       
   342 
       
   343 \idx{SUM_Un_distrib2}    (SUM x:C. A(x) Un B(x)) =
       
   344                    (SUM x:C. A(x)) Un (SUM x:C. B(x))
       
   345 
       
   346 \idx{SUM_Int_distrib1}   (SUM x:A Int B. C(x)) =
       
   347                    (SUM x:A. C(x)) Int (SUM x:B. C(x))
       
   348 
       
   349 \idx{SUM_Int_distrib2}   (SUM x:C. A(x) Int B(x)) =
       
   350                    (SUM x:C. A(x)) Int (SUM x:C. B(x))
       
   351 
       
   352 
       
   353 ----------------------------------------------------------------
       
   354 perm.ML
       
   355 
       
   356 \idx{comp_def}
       
   357         r O s == \{xz : domain(s)*range(r) . 
       
   358                   EX x y z. xz=<x,z> & <x,y>:s & <y,z>:r\}),
       
   359 \idx{id_def}                    (*the identity function for A*)
       
   360         id(A) == (lam x:A. x)),
       
   361 \idx{inj_def} 
       
   362         inj(A,B) == 
       
   363             \{ f: A->B. ALL w:A. ALL x:A. f`w=f`x --> w=x\}),
       
   364 \idx{surj_def} 
       
   365         surj(A,B) == \{ f: A->B . ALL y:B. EX x:A. f`x=y\}),
       
   366 \idx{bij_def}
       
   367         bij(A,B) == inj(A,B) Int surj(A,B))
       
   368 
       
   369 
       
   370 \idx{surj_is_fun}        f: surj(A,B) ==> f: A->B
       
   371 \idx{fun_is_surj}        f : Pi(A,B) ==> f: surj(A,range(f))
       
   372 
       
   373 \idx{inj_is_fun}         f: inj(A,B) ==> f: A->B
       
   374 \idx{inj_equality}       [| <a,b>:f;  <c,b>:f;  f: inj(A,B) |] ==> a=c
       
   375 
       
   376 \idx{bij_is_fun}         f: bij(A,B) ==> f: A->B
       
   377 
       
   378 \idx{inj_converse_surj}  f: inj(A,B) ==> converse(f): surj(range(f), A)
       
   379 
       
   380 \idx{left_inverse}       [| f: inj(A,B);  a: A |] ==> converse(f)`(f`a) = a
       
   381 \idx{right_inverse}      [| f: inj(A,B);  b: range(f) |] ==> 
       
   382                    f`(converse(f)`b) = b
       
   383 
       
   384 \idx{inj_converse_inj}   f: inj(A,B) ==> converse(f): inj(range(f), A)
       
   385 \idx{bij_converse_bij}   f: bij(A,B) ==> converse(f): bij(B,A)
       
   386 
       
   387 \idx{comp_type}          [| s<=A*B;  r<=B*C |] ==> (r O s) <= A*C
       
   388 \idx{comp_assoc}         (r O s) O t = r O (s O t)
       
   389 
       
   390 \idx{left_comp_id}       r<=A*B ==> id(B) O r = r
       
   391 \idx{right_comp_id}      r<=A*B ==> r O id(A) = r
       
   392 
       
   393 \idx{comp_func}          [| g: A->B;  f: B->C |] ==> (f O g) : A->C
       
   394 \idx{comp_func_apply}    [| g: A->B;  f: B->C;  a:A |] ==> (f O g)`a = f`(g`a)
       
   395 
       
   396 \idx{comp_inj}      [| g: inj(A,B);   f: inj(B,C)  |] ==> (f O g) : inj(A,C)
       
   397 \idx{comp_surj}     [| g: surj(A,B);  f: surj(B,C) |] ==> (f O g) : surj(A,C)
       
   398 \idx{comp_bij}      [| g: bij(A,B);  f: bij(B,C) |] ==> (f O g) : bij(A,C)
       
   399 
       
   400 \idx{left_comp_inverse}     f: inj(A,B) ==> converse(f) O f = id(A)
       
   401 \idx{right_comp_inverse}    f: surj(A,B) ==> f O converse(f) = id(B)
       
   402 
       
   403 \idx{bij_disjoint_Un}   
       
   404     [| f: bij(A,B);  g: bij(C,D);  A Int C = 0;  B Int D = 0 |] ==> 
       
   405     (f Un g) : bij(A Un C, B Un D)
       
   406 
       
   407 \idx{restrict_bij}  [| f: inj(A,B);  C<=A |] ==> restrict(f,C): bij(C, f``C)
       
   408 
       
   409 
       
   410 ----------------------------------------------------------------
       
   411 plus.ML
       
   412 
       
   413 \idx{plus_def}      A+B == \{0\}*A Un \{\{0\}\}*B
       
   414 \idx{Inl_def}       Inl(a) == < 0 ,a>
       
   415 \idx{Inr_def}       Inr(b) == <\{0\},b>
       
   416 \idx{when_def}      when(u,c,d) == 
       
   417                 THE y. EX z.(u=Inl(z) & y=c(z)) | (u=Inr(z) & y=d(z))
       
   418 
       
   419 \idx{plus_InlI}     a : A ==> Inl(a) : A+B
       
   420 \idx{plus_InrI}     b : B ==> Inr(b) : A+B
       
   421 
       
   422 \idx{Inl_inject}    Inl(a) = Inl(b) ==>  a=b
       
   423 \idx{Inr_inject}    Inr(a) = Inr(b) ==> a=b
       
   424 \idx{Inl_neq_Inr}   Inl(a)=Inr(b) ==> P
       
   425 
       
   426 \idx{plusE2}        u: A+B ==> (EX x. x:A & u=Inl(x)) | (EX y. y:B & u=Inr(y))
       
   427 
       
   428 \idx{when_Inl_conv} when(Inl(a),c,d) = c(a)
       
   429 \idx{when_Inr_conv} when(Inr(b),c,d) = d(b)
       
   430 
       
   431 \idx{when_type}     [| u: A+B; 
       
   432                  !!x. x: A ==> c(x): C(Inl(x));   
       
   433                  !!y. y: B ==> d(y): C(Inr(y)) 
       
   434               |] ==> when(u,c,d) : C(u)
       
   435 
       
   436 
       
   437 ----------------------------------------------------------------
       
   438 nat.ML
       
   439 
       
   440 
       
   441 \idx{nat_def}       nat == lfp(lam r: Pow(Inf). \{0\} Un RepFun(r,succ))
       
   442 \idx{nat_case_def}  nat_case(n,a,b) == 
       
   443                 THE y. n=0 & y=a | (EX x. n=succ(x) & y=b(x))
       
   444 \idx{nat_rec_def}   nat_rec(k,a,b) == 
       
   445                 transrec(nat, k, %n f. nat_case(n, a, %m. b(m, f`m)))
       
   446 
       
   447 \idx{nat_0_I}       0 : nat
       
   448 \idx{nat_succ_I}    n : nat ==> succ(n) : nat
       
   449 
       
   450 \idx{nat_induct}        
       
   451     [| n: nat;  P(0);  !!x. [| x: nat;  P(x) |] ==> P(succ(x)) 
       
   452     |] ==> P(n)
       
   453 
       
   454 \idx{nat_case_0_conv}       nat_case(0,a,b) = a
       
   455 \idx{nat_case_succ_conv}    nat_case(succ(m),a,b) = b(m)
       
   456 
       
   457 \idx{nat_case_type}     
       
   458     [| n: nat;  a: C(0);  !!m. m: nat ==> b(m): C(succ(m))  
       
   459     |] ==> nat_case(n,a,b) : C(n)
       
   460 
       
   461 \idx{nat_rec_0_conv}        nat_rec(0,a,b) = a
       
   462 \idx{nat_rec_succ_conv}     m: nat ==> nat_rec(succ(m),a,b) = b(m, nat_rec(m,a,b))
       
   463 
       
   464 \idx{nat_rec_type}      
       
   465     [| n: nat;  
       
   466        a: C(0);  
       
   467        !!m z. [| m: nat;  z: C(m) |] ==> b(m,z): C(succ(m))  
       
   468     |] ==> nat_rec(n,a,b) : C(n)