Logical.Unsafe
type state = {
rstate : P.e;
ustate : P.u;
wstate : P.w;
sstate : P.s;
}
val make : ('a, state, state, Exninfo.iexn) BackState.t -> 'a t
val repr : 'a t -> ('a, state, state, Exninfo.iexn) BackState.t