src/HOLCF/IOA/NTP/Packet.thy
changeset 25131 2c8caac48ade
parent 19739 c58ef2aa5430
child 35174 e15040ae75d7
equal deleted inserted replaced
25130:d91391a8705b 25131:2c8caac48ade
     8 begin
     8 begin
     9 
     9 
    10 types
    10 types
    11   'msg packet = "bool * 'msg"
    11   'msg packet = "bool * 'msg"
    12 
    12 
    13 constdefs
    13 definition
    14 
    14   hdr :: "'msg packet => bool" where
    15   hdr  :: "'msg packet => bool"
       
    16   "hdr == fst"
    15   "hdr == fst"
    17 
    16 
    18   msg :: "'msg packet => 'msg"
    17 definition
       
    18   msg :: "'msg packet => 'msg" where
    19   "msg == snd"
    19   "msg == snd"
    20 
    20 
    21 
    21 
    22 text {* Instantiation of a tautology? *}
    22 text {* Instantiation of a tautology? *}
    23 lemma eq_packet_imp_eq_hdr: "!x. x = packet --> hdr(x) = hdr(packet)"
    23 lemma eq_packet_imp_eq_hdr: "!x. x = packet --> hdr(x) = hdr(packet)"