↰
base.caps.IsoViewer[T,R]base.caps.CapTries/0base.caps.CapTry/0base.caps.Create/0base.caps.Env/0base.caps.FEnv/0base.caps.FRandomSeed/0base.caps.FileHandleMode/0base.caps.IO/0base.caps.IsoConsumer/2base.caps.IsoPod/0base.caps.IsoPod/1base.caps.IsoViewer/2base.caps.RandomSeed/0base.caps.Read/0base.caps.System/0base.caps.TryBody/1base.caps.TryBody/2base.caps.UnrestrictedIO/0base.caps.Write/0mut .some(x: readH T): R,
mut .empty: R,mut .some(x: readH T): R,
mut .empty: R,