Module Share : SHARE_MODEL := tree_shares.Share.Definition share : Type := Share.t.Instance pa_share : Perm_alg share := Share.pa.Instance sa_share : Sep_alg share := Share.sa.Instance ca_share : Canc_alg share := Share.ca.Definition emptyshare : share := Share.bot.Definition fullshare : share := Share.top.

Theorem leq_join_sub : forall s1 s2:Share.t, s1 <= s2 <-> join_sub s1 s2.