添加Option转换到Either的支持

Sanchime.Functional/Core/Extensions/Option.cs

@@ -96,6 +96,17 @@ public static class OptionExtension
     public static Option<T> OrElse<T>(this Option<T> left, Func<Option<T>> right)
         => left.Match(() => right(), (_) => left);
 
+    /// <summary>
+    /// 将<see cref="Option"转为<see cref="Either"/>
+    /// </summary>
+    /// <param name="option"></param>
+    /// <param name="error"></param>
+    /// <typeparam name="L"></typeparam>
+    /// <typeparam name="R"></typeparam>
+    /// <returns></returns>
+    public static Either<L, R> ToEither<L, R>(this Option<L> option, R error)
+        => option.IsSome() ? Either.Right(error) : Either.Left(option.Value);
+
     #region Linq式
 
     public static Option<R> Select<T, R>(this Option<T> source, Func<T, R> mapping)

Sanchime.Functional/Core/Products/Option.cs

@@ -26,7 +26,6 @@ public static class Option
 
 public readonly struct Option<TValue> : IEquatable<None>, IEquatable<Option<TValue>>
 {
-
     private readonly TValue _value;
 
     private readonly bool _isSome;
@@ -57,11 +56,19 @@ public readonly struct Option<TValue> : IEquatable<None>, IEquatable<Option<TVal
     public static implicit operator Option<TValue>(TValue value)
         => value is null ? Option.None : Option.Some(value);
 
+    public bool IsSome() => this.Match(()  => false, (_) => true);
 
-    internal bool IsSome() => this.Match(()  => false, (_) => true);
-
-    internal TValue ValueUnsafe => this.Match(() => throw new InvalidOperationException(), val => val);
+    /// <summary>
+    /// 获取<see cref="Option"/>内部的值，如果为<see cref="Option.None"/>则抛出异常
+    /// </summary>
+    /// <returns></returns>
+    public TValue ValueUnsafe => this.Match(() => throw new InvalidOperationException(), val => val);
 
+    /// <summary>
+    /// 获取<see cref="Option"/>内部的值，如果为<see cref="Option.None"/>则返回默认值
+    /// </summary>
+    /// <returns></returns>
+    public TValue Value => this.Match(() => default!, val => val);
 
     /// <summary>
     /// 转换为序列