src/HOLCF/IOA/NTP/Packet.thy
author blanchet
Wed, 14 Apr 2010 18:23:51 +0200
changeset 36142 f5e15e9aae10
parent 35174 e15040ae75d7
permissions -rw-r--r--
make Sledgehammer "minimize" output less confusing + round up (not down) time limits to nearest second

(*  Title:      HOL/IOA/NTP/Packet.thy
    Author:     Tobias Nipkow & Konrad Slind
*)

theory Packet
imports Multiset
begin

types
  'msg packet = "bool * 'msg"

definition
  hdr :: "'msg packet => bool" where
  "hdr == fst"

definition
  msg :: "'msg packet => 'msg" where
  "msg == snd"


text {* Instantiation of a tautology? *}
lemma eq_packet_imp_eq_hdr: "!x. x = packet --> hdr(x) = hdr(packet)"
  by simp

declare hdr_def [simp] msg_def [simp]

end