= MLtonMonoVector

[source,sml]
----
signature MLTON_MONO_VECTOR =
   sig
      type t
      type elem
      val fromPoly: elem vector -> t
      val toPoly: t -> elem vector
   end
----

* `type t`
+
type of monomorphic vector

* `type elem`
+
type of vector elements

* `fromPoly v`
+
type cast a polymorphic vector to its monomorphic counterpart; in
MLton, this is a constant-time operation

* `toPoly v`
+
type cast a monomorphic vector to its polymorphic counterpart; in
MLton, this is a constant-time operation
