val record_trace : 'a Logical.t -> 'a Logical.trecord_trace t behaves like t and compute its info trace.
val update : (Info.state -> Info.state) -> unit Logical.tval opn : Info.tag -> unit Logical.tval close : unit Logical.tval leaf : Info.tag -> unit Logical.tval tag : Info.tag -> 'a Logical.t -> 'a Logical.ttag a t opens tag a runs t then closes the tag.