↰ mut base.repr.Repr[T]

• base.repr.FRepr/1
• base.repr.Repr/1

read .look[R$0](f: read base.F[read T,imm R$0]): imm R$0 -> …,
read .cached[R$0](f: imm base.F[read T,imm R$0]): imm R$0 -> …,
mut .mutate[R$0](f: read base.F[mut T,imm R$0]): imm R$0 -> …,
mut .reset: imm base.Void -> …,