src/HOL/Sum.ML
changeset 3091 9366415b93ad
parent 2922 580647a879cf
child 3842 b55686a7b22c
equal deleted inserted replaced
3090:eeb4d0c7f748 3091:9366415b93ad
   121 goalw Sum.thy [sum_case_def] "sum_case f g (Inl x) = f(x)";
   121 goalw Sum.thy [sum_case_def] "sum_case f g (Inl x) = f(x)";
   122 by (blast_tac (!claset addIs [select_equality]) 1);
   122 by (blast_tac (!claset addIs [select_equality]) 1);
   123 qed "sum_case_Inl";
   123 qed "sum_case_Inl";
   124 
   124 
   125 goalw Sum.thy [sum_case_def] "sum_case f g (Inr x) = g(x)";
   125 goalw Sum.thy [sum_case_def] "sum_case f g (Inr x) = g(x)";
   126 by (fast_tac (!claset addIs [select_equality]) 1);
   126 by (blast_tac (!claset addIs [select_equality]) 1);
   127 qed "sum_case_Inr";
   127 qed "sum_case_Inr";
   128 
   128 
   129 Addsimps [sum_case_Inl, sum_case_Inr];
   129 Addsimps [sum_case_Inl, sum_case_Inr];
   130 
   130 
   131 (** Exhaustion rule for sums -- a degenerate form of induction **)
   131 (** Exhaustion rule for sums -- a degenerate form of induction **)