vkhorikov#317 Add non-generic Maybe.None

Author: Razenpok

CSharpFunctionalExtensions.Tests/MaybeTests/BasicTests.cs

@@ -126,6 +126,15 @@ public void Maybe_From_without_type_parameter_creates_new_maybe()
  withoutTypeParam.Should().NotBe(differentValueTypeParam);
  }
 
+ [Fact]
+ public void Can_cast_non_generic_maybe_none_to_maybe_none()
+ {
+ Maybe<int> maybe = Maybe.None;
+
+ maybe.HasValue.Should().BeFalse();
+ maybe.HasNoValue.Should().BeTrue();
+ }
+
  private class MyClass
  {
  public override string ToString()

CSharpFunctionalExtensions/Maybe/Maybe.cs

@@ -47,6 +47,8 @@ public static implicit operator Maybe<T>(T value)
  return new Maybe<T>(value);
  }
 
+ public static implicit operator Maybe<T>(Maybe value) => None;
+
  public static Maybe<T> From(T obj)
  {
  return new Maybe<T>(obj);
@@ -127,10 +129,12 @@ public override string ToString()
  }
 
  /// <summary>
- /// Non-generic entrypoint for <see cref="Maybe{T}" /> methods
+ /// Non-generic entrypoint for <see cref="Maybe{T}" /> members
  /// </summary>
- public static class Maybe
+ public struct Maybe
  {
+ public static Maybe None => new Maybe();
+
  /// <summary>
  /// Creates a new <see cref="Maybe{T}" /> from the provided <paramref name="value"/>
  /// </summary>