src/HOL/Product_Type.thy
changeset 61630 608520e0e8e2
parent 61425 fb95d06fb21f
child 61799 4cf66f21b764
equal deleted inserted replaced
61629:90f54d9e63f2 61630:608520e0e8e2
  1142 
  1142 
  1143 lemma Sigma_Union:
  1143 lemma Sigma_Union:
  1144   "Sigma (\<Union>X) B = (\<Union>A\<in>X. Sigma A B)"
  1144   "Sigma (\<Union>X) B = (\<Union>A\<in>X. Sigma A B)"
  1145   by blast
  1145   by blast
  1146 
  1146 
       
  1147 lemma Pair_vimage_Sigma: "Pair x -` Sigma A f = (if x \<in> A then f x else {})"
       
  1148   by auto
       
  1149 
  1147 text \<open>
  1150 text \<open>
  1148   Non-dependent versions are needed to avoid the need for higher-order
  1151   Non-dependent versions are needed to avoid the need for higher-order
  1149   matching, especially when the rules are re-oriented.
  1152   matching, especially when the rules are re-oriented.
  1150 \<close>
  1153 \<close>
  1151 
  1154