Program Definition juicy_mem_store j ch b ofs v: option juicy_mem :=
  if valid_access_dec (m_dry j) ch b ofs Writable
    then Some (store_juicy_mem j _ ch b ofs v _)
    else None.

Lemma juicy_mem_store_succeeds: forall j j' ch b ofs v, juicy_mem_store j ch b ofs v = Some j' -> exists m', store ch (m_dry j) b ofs v = Some m' /\ m' = m_dry j'.