Module EnvSA.
Existing Instance Join_env.
Existing Instance Perm_env.
Existing Instance Sep_env.
Existing Instance Sing_env.
Existing Instance Canc_env.
Existing Instance Disj_env.
Existing Instance Cross_env.
Hint Resolve @empty_env_unit @empty_env_unit' : core.

Lemma identity_empty_env {key: Type}{A: Type}{KE: EqDec key}:  forall rho: env key A, identity rho <-> rho = empty_env.