export interface OptionFromNullableC<C extends t.Mixed>
  extends t.Type<O.Option<t.TypeOf<C>>, t.OutputOf<C> | null, unknown> {}

export function optionFromNullable<C extends t.Mixed>(
  codec: C,
  name: string = `Option<${codec.name}>`
): OptionFromNullableC<C> { ... }