Light.MSourceval merkle_tree :
Tezos_proxy.Proxy.proxy_getter_input ->
Tezos_protocol_environment.Proxy_context.M.key ->
Tezos_proxy.Light_proto.Proof.merkle_leaf_kind ->
Tezos_proxy.Light_proto.Proof.tree Tezos_proxy.Light_proto.Proof.t option
Tezos_base.TzPervasives.tzresult
Lwt.t