src/HOL/String.thy
changeset 70340 7383930fc946
parent 69906 55534affe445
child 71094 a197532693a5
equal deleted inserted replaced
70339:e939ea997f5f 70340:7383930fc946
    43     foldr (\<lambda>b k. of_bool b + k * 2) [b0, b1, b2, b3, b4, b5, b6, b7] 0"
    43     foldr (\<lambda>b k. of_bool b + k * 2) [b0, b1, b2, b3, b4, b5, b6, b7] 0"
    44   by (simp add: of_char_def ac_simps)
    44   by (simp add: of_char_def ac_simps)
    45 
    45 
    46 end
    46 end
    47 
    47 
    48 context semiring_parity
    48 context unique_euclidean_semiring_with_nat
    49 begin
    49 begin
    50 
    50 
    51 definition char_of :: "'a \<Rightarrow> char"
    51 definition char_of :: "'a \<Rightarrow> char"
    52   where "char_of n = Char (odd n) (odd (drop_bit 1 n))
    52   where "char_of n = Char (odd n) (odd (drop_bit 1 n))
    53     (odd (drop_bit 2 n)) (odd (drop_bit 3 n))
    53     (odd (drop_bit 2 n)) (odd (drop_bit 3 n))