如何避免重复声明类似的类型？

Question

我有以下代码：

type CapturablePieces = Pawn | Knight | Bishop | Rook | Queen

我可以按如下方式定义另一种类型：

type Pieces = Pawn | Knight | Bishop | Rook | Queen | King

然而，这里显然有很多代码重复。有没有办法通过将CapturablePieces纳入Pieces？

的定义来避免这种情况

Answer 1

如果你不需要CapturablePieces是可分离的类型，只是某些特定情况的子集，也许它可以作为成员实现？我可以想到两种方式：

a）静态成员中可捕捉片段的集合：

type Pieces = Pawn | Knight | Bishop | Rook | Queen | King
    static member Capturable = [Pawn; Knight; Bishop; Rook; Queen]

b）布尔成员：

type Pieces = Pawn | Knight | Bishop | Rook | Queen | King
    member x.IsCapturable = match x with King -> false | _ -> true