src/HOL/Library/Product_plus.thy
changeset 54230 b1d955791529
parent 51301 6822aa82aafa
child 57512 cc97b347b301
equal deleted inserted replaced
54229:ca638d713ff8 54230:b1d955791529
   102 
   102 
   103 instance prod ::
   103 instance prod ::
   104   (cancel_comm_monoid_add, cancel_comm_monoid_add) cancel_comm_monoid_add ..
   104   (cancel_comm_monoid_add, cancel_comm_monoid_add) cancel_comm_monoid_add ..
   105 
   105 
   106 instance prod :: (group_add, group_add) group_add
   106 instance prod :: (group_add, group_add) group_add
   107   by default (simp_all add: prod_eq_iff diff_minus)
   107   by default (simp_all add: prod_eq_iff)
   108 
   108 
   109 instance prod :: (ab_group_add, ab_group_add) ab_group_add
   109 instance prod :: (ab_group_add, ab_group_add) ab_group_add
   110   by default (simp_all add: prod_eq_iff)
   110   by default (simp_all add: prod_eq_iff)
   111 
   111 
   112 lemma fst_setsum: "fst (\<Sum>x\<in>A. f x) = (\<Sum>x\<in>A. fst (f x))"
   112 lemma fst_setsum: "fst (\<Sum>x\<in>A. f x) = (\<Sum>x\<in>A. fst (f x))"