src/HOLCF/Discrete.ML

moved inj and surj from Set to Fun and Inv -> inv.

(*  Title:      HOLCF/Discrete.ML
    ID:         $Id$
    Author:     Tobias Nipkow
    Copyright   1997 TUM
*)

goalw thy [undiscr_def] "undiscr(Discr x) = x";
by(Simp_tac 1);
qed "undiscr_Discr";
Addsimps [undiscr_Discr];

goal thy
 "!!S::nat=>('a::term)discr. is_chain(S) ==> range(%i.f(S i)) = {f(S 0)}";
by(fast_tac (!claset addDs [discr_chain0] addEs [arg_cong]) 1);
qed "discr_chain_f_range0";

goalw thy [cont,is_lub,is_ub] "cont(%x::('a::term)discr.f x)";
by(simp_tac (!simpset addsimps [discr_chain_f_range0]) 1);
qed "cont_discr";
AddIffs [cont_discr];