调整Option

Sanchime.Functional/Extensions/Option.cs

@@ -2,31 +2,10 @@ namespace Sanchime.Functional.Extensions;
 
 public static class OptionExtension
 {
-    
-
-    #region 函子: 同一范畴内不同对象之间的态射
-
-    // public static Option<R> Map<T, R>(this None _, Func<T, R> mapping)
-    //     => Option.None;
-
-    // public static Option<R> Map<T, R>(this Some<T> some, Func<T, R> mapping)
-    //     => Option.Some(mapping(some.Value));
-
-    // public static Option<R> Map<T, R>(this Option<T> option, Func<T, R> mapping)
-    //     => option.Match(() => Option.None, (val) => Option.Some(mapping(val)));
-
-    // public static IOption Map<T1, T2, R>(this Option<T1> option, Func<T1, T2, R> mapping)
-    //     => option.Map(mapping.Curry());
-
-    // public static IOption Map<T1, T2, T3, R>(this Option<T1> option, Func<T1, T2, T3, R> mapping)
-    //     => option.Map(mapping.CurryFirst());
-    #endregion
-
     #region 单子: 自函子范畴上的幺半群
 
 
-    public static Option<R> Bind<T, R>(this Option<T> option, Func<T, Option<R>> binding)
+    
-        => option.Match(() => new Option<R>(), binding);
 
     public static IEnumerable<R> Bind<T1, T2, R>(this Option<T1> option, Func<T1, IEnumerable<R>> binding)
         => option.AsEnumerable().Bind(binding);

Sanchime.Functional/Products/Options/None.cs

@@ -3,12 +3,13 @@ namespace Sanchime.Functional.Products;
 /// <summary>
 /// <see cref="Optional"/>的<see cref="None"/>状态
 /// </summary>
-public readonly partial struct None : IOption
+public readonly partial struct None : IOption<Unit>
 {
-    /// <summary>
+    public None()
-    /// 静态构造形成单例
+    {
-    /// </summary>
+        
-    static None() { }
+    }
     public bool IsSome => false;
     internal static readonly None Default = new();
+    public Unit Value { get; } = Unit.Value;
 }

Sanchime.Functional/Products/Options/OptionMonad.cs

@@ -13,4 +13,7 @@ public readonly partial struct Option<TValue>
 
     public static IOption Return(TValue value) 
         => Return<TValue>(value);
+    
+    public Option<TResult> Bind<TResult>(Func<TValue, Option<TResult>> binder)
+        => this.Match(() => new Option<TResult>(), binder);
 }