doc-src/TutorialI/Sets/Examples.thy
changeset 10294 2ec9c808a8a7
child 10341 6eb91805a012
     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/doc-src/TutorialI/Sets/Examples.thy	Mon Oct 23 16:24:52 2000 +0200
     1.3 @@ -0,0 +1,278 @@
     1.4 +theory Examples = Main:
     1.5 +
     1.6 +ML "reset eta_contract"
     1.7 +ML "Pretty.setmargin 64"
     1.8 +
     1.9 +text{*membership, intersection *}
    1.10 +text{*difference and empty set*}
    1.11 +text{*complement, union and universal set*}
    1.12 +
    1.13 +lemma "(x \<in> A \<inter> B) = (x \<in> A \<and> x \<in> B)"
    1.14 +  apply (blast)
    1.15 +  done
    1.16 +
    1.17 +text{*
    1.18 +@{thm[display] IntI[no_vars]}
    1.19 +\rulename{IntI}
    1.20 +
    1.21 +@{thm[display] IntD1[no_vars]}
    1.22 +\rulename{IntD1}
    1.23 +
    1.24 +@{thm[display] IntD2[no_vars]}
    1.25 +\rulename{IntD2}
    1.26 +*}
    1.27 +
    1.28 +lemma "(x \<in> -A) = (x \<notin> A)"
    1.29 +  apply (blast)
    1.30 +  done
    1.31 +
    1.32 +text{*
    1.33 +@{thm[display] Compl_iff[no_vars]}
    1.34 +\rulename{Compl_iff}
    1.35 +*}
    1.36 +
    1.37 +lemma "- (A \<union> B) = -A \<inter> -B"
    1.38 +  apply (blast)
    1.39 +  done
    1.40 +
    1.41 +text{*
    1.42 +@{thm[display] Compl_Un[no_vars]}
    1.43 +\rulename{Compl_Un}
    1.44 +*}
    1.45 +
    1.46 +lemma "A-A = {}"
    1.47 +  apply (blast)
    1.48 +  done
    1.49 +
    1.50 +text{*
    1.51 +@{thm[display] Diff_disjoint[no_vars]}
    1.52 +\rulename{Diff_disjoint}
    1.53 +*}
    1.54 +
    1.55 +  
    1.56 +
    1.57 +lemma "A \<union> -A = UNIV"
    1.58 +  apply (blast)
    1.59 +  done
    1.60 +
    1.61 +text{*
    1.62 +@{thm[display] Compl_partition[no_vars]}
    1.63 +\rulename{Compl_partition}
    1.64 +*}
    1.65 +
    1.66 +text{*subset relation*}
    1.67 +
    1.68 +
    1.69 +text{*
    1.70 +@{thm[display] subsetI[no_vars]}
    1.71 +\rulename{subsetI}
    1.72 +
    1.73 +@{thm[display] subsetD[no_vars]}
    1.74 +\rulename{subsetD}
    1.75 +*}
    1.76 +
    1.77 +lemma "((A \<union> B) \<subseteq> C) = (A \<subseteq> C \<and> B \<subseteq> C)"
    1.78 +  apply (blast)
    1.79 +  done
    1.80 +
    1.81 +text{*
    1.82 +@{thm[display] Un_subset_iff[no_vars]}
    1.83 +\rulename{Un_subset_iff}
    1.84 +*}
    1.85 +
    1.86 +lemma "(A \<subseteq> -B) = (B \<subseteq> -A)"
    1.87 +  apply (blast)
    1.88 +  done
    1.89 +
    1.90 +lemma "(A <= -B) = (B <= -A)"
    1.91 +  oops
    1.92 +
    1.93 +text{*ASCII version: blast fails because of overloading because
    1.94 + it doesn't have to be sets*}
    1.95 +
    1.96 +lemma "((A:: 'a set) <= -B) = (B <= -A)"
    1.97 +  apply (blast)
    1.98 +  done
    1.99 +
   1.100 +text{*A type constraint lets it work*}
   1.101 +
   1.102 +text{*An issue here: how do we discuss the distinction between ASCII and
   1.103 +X-symbol notation?  Here the latter disambiguates.*}
   1.104 +
   1.105 +
   1.106 +text{*
   1.107 +set extensionality
   1.108 +
   1.109 +@{thm[display] set_ext[no_vars]}
   1.110 +\rulename{set_ext}
   1.111 +
   1.112 +@{thm[display] equalityI[no_vars]}
   1.113 +\rulename{equalityI}
   1.114 +
   1.115 +@{thm[display] equalityE[no_vars]}
   1.116 +\rulename{equalityE}
   1.117 +*}
   1.118 +
   1.119 +
   1.120 +text{*finite sets: insertion and membership relation*}
   1.121 +text{*finite set notation*}
   1.122 +
   1.123 +lemma "insert x A = {x} \<union> A"
   1.124 +  apply (blast)
   1.125 +  done
   1.126 +
   1.127 +text{*
   1.128 +@{thm[display] insert_is_Un[no_vars]}
   1.129 +\rulename{insert_is_Un}
   1.130 +*}
   1.131 +
   1.132 +lemma "{a,b} \<union> {c,d} = {a,b,c,d}"
   1.133 +  apply (blast)
   1.134 +  done
   1.135 +
   1.136 +lemma "{a,b} \<inter> {b,c} = {b}"
   1.137 +  apply (auto)
   1.138 +  oops
   1.139 +text{*fails because it isn't valid*}
   1.140 +
   1.141 +lemma "{a,b} \<inter> {b,c} = (if a=c then {a,b} else {b})"
   1.142 +  apply (simp)
   1.143 +  apply (blast)
   1.144 +  done
   1.145 +
   1.146 +text{*or just force or auto.  blast alone can't handle the if-then-else*}
   1.147 +
   1.148 +text{*next: some comprehension examples*}
   1.149 +
   1.150 +lemma "(a \<in> {z. P z}) = P a"
   1.151 +  apply (blast)
   1.152 +  done
   1.153 +
   1.154 +text{*
   1.155 +@{thm[display] mem_Collect_eq[no_vars]}
   1.156 +\rulename{mem_Collect_eq}
   1.157 +*}
   1.158 +
   1.159 +lemma "{x. x \<in> A} = A"
   1.160 +  apply (blast)
   1.161 +  done
   1.162 +  
   1.163 +text{*
   1.164 +@{thm[display] Collect_mem_eq[no_vars]}
   1.165 +\rulename{Collect_mem_eq}
   1.166 +*}
   1.167 +
   1.168 +lemma "{x. P x \<or> x \<in> A} = {x. P x} \<union> A"
   1.169 +  apply (blast)
   1.170 +  done
   1.171 +
   1.172 +lemma "{x. P x \<longrightarrow> Q x} = -{x. P x} \<union> {x. Q x}"
   1.173 +  apply (blast)
   1.174 +  done
   1.175 +
   1.176 +constdefs
   1.177 +  prime   :: "nat set"
   1.178 +    "prime == {p. 1<p & (ALL m. m dvd p --> m=1 | m=p)}"
   1.179 +
   1.180 +lemma "{p*q | p q. p\<in>prime \<and> q\<in>prime} = 
   1.181 +       {z. \<exists>p q. z = p*q \<and> p\<in>prime \<and> q\<in>prime}"
   1.182 +  apply (blast)
   1.183 +  done
   1.184 +
   1.185 +text{*binders*}
   1.186 +
   1.187 +text{*bounded quantifiers*}
   1.188 +
   1.189 +lemma "(\<exists>x\<in>A. P x) = (\<exists>x. x\<in>A \<and> P x)"
   1.190 +  apply (blast)
   1.191 +  done
   1.192 +
   1.193 +text{*
   1.194 +@{thm[display] bexI[no_vars]}
   1.195 +\rulename{bexI}
   1.196 +*}
   1.197 +
   1.198 +text{*
   1.199 +@{thm[display] bexE[no_vars]}
   1.200 +\rulename{bexE}
   1.201 +*}
   1.202 +
   1.203 +lemma "(\<forall>x\<in>A. P x) = (\<forall>x. x\<in>A \<longrightarrow> P x)"
   1.204 +  apply (blast)
   1.205 +  done
   1.206 +
   1.207 +text{*
   1.208 +@{thm[display] ballI[no_vars]}
   1.209 +\rulename{ballI}
   1.210 +*}
   1.211 +
   1.212 +text{*
   1.213 +@{thm[display] bspec[no_vars]}
   1.214 +\rulename{bspec}
   1.215 +*}
   1.216 +
   1.217 +text{*indexed unions and variations*}
   1.218 +
   1.219 +lemma "(\<Union>x. B x) = (\<Union>x\<in>UNIV. B x)"
   1.220 +  apply (blast)
   1.221 +  done
   1.222 +
   1.223 +text{*
   1.224 +@{thm[display] UN_iff[no_vars]}
   1.225 +\rulename{UN_iff}
   1.226 +*}
   1.227 +
   1.228 +text{*
   1.229 +@{thm[display] Union_iff[no_vars]}
   1.230 +\rulename{Union_iff}
   1.231 +*}
   1.232 +
   1.233 +lemma "(\<Union>x\<in>A. B x) = {y. \<exists>x\<in>A. y \<in> B x}"
   1.234 +  apply (blast)
   1.235 +  done
   1.236 +
   1.237 +lemma "\<Union>S = (\<Union>x\<in>S. x)"
   1.238 +  apply (blast)
   1.239 +  done
   1.240 +
   1.241 +text{*
   1.242 +@{thm[display] UN_I[no_vars]}
   1.243 +\rulename{UN_I}
   1.244 +*}
   1.245 +
   1.246 +text{*
   1.247 +@{thm[display] UN_E[no_vars]}
   1.248 +\rulename{UN_E}
   1.249 +*}
   1.250 +
   1.251 +text{*indexed intersections*}
   1.252 +
   1.253 +lemma "(\<Inter>x. B x) = {y. \<forall>x. y \<in> B x}"
   1.254 +  apply (blast)
   1.255 +  done
   1.256 +
   1.257 +text{*
   1.258 +@{thm[display] INT_iff[no_vars]}
   1.259 +\rulename{INT_iff}
   1.260 +*}
   1.261 +
   1.262 +text{*
   1.263 +@{thm[display] Inter_iff[no_vars]}
   1.264 +\rulename{Inter_iff}
   1.265 +*}
   1.266 +
   1.267 +text{*mention also card, Pow, etc.*}
   1.268 +
   1.269 +
   1.270 +text{*
   1.271 +@{thm[display] card_Un_Int[no_vars]}
   1.272 +\rulename{card_Un_Int}
   1.273 +
   1.274 +@{thm[display] card_Pow[no_vars]}
   1.275 +\rulename{card_Pow}
   1.276 +
   1.277 +@{thm[display] n_subsets[no_vars]}
   1.278 +\rulename{n_subsets}
   1.279 +*}
   1.280 +
   1.281 +end