src/HOL/SPARK/Examples/RIPEMD-160/R_L.thy
author haftmann
Fri, 27 Jun 2025 08:09:26 +0200
changeset 82775 61c39a9e5415
parent 69605 a96320074298
permissions -rw-r--r--
typo

(*  Title:      HOL/SPARK/Examples/RIPEMD-160/R_L.thy
    Author:     Fabian Immler, TU Muenchen

Verification of the RIPEMD-160 hash function
*)

theory R_L
imports RMD_Specification RMD_Lemmas
begin

spark_open \<open>rmd/r_l\<close>

spark_vc function_r_l_2
proof -
  from \<open>0 \<le> j\<close> \<open>j \<le> 79\<close>
  show C: ?C1
    by (simp add: r_def r_list_def nth_map [symmetric, of _ _ int] del: fun_upd_apply)
      (simp add: nth_fun_of_list_eq [of _ _ undefined] del: fun_upd_apply)
  from C show ?C2 by simp
  have "list_all (\<lambda>n. int n \<le> 15) r_list"
    by (simp add: r_list_def)
  moreover have "length r_list = 80"
    by (simp add: r_list_def)
  ultimately show ?C3 unfolding C using \<open>j \<le> 79\<close>
    by (simp add: r_def list_all_length)
qed

spark_end

end