<PropertyGroup>
        <MSBuildAllProjects>$(MSBuildAllProjects);$(Nemerle)\Nemerle.MSBuild.targets</MSBuildAllProjects>
        <DefaultLanguageSourceExtension>.cs</DefaultLanguageSourceExtension> <!-- .n -->
        <Language>C#</Language>  <!-- Nemerle -->
    </PropertyGroup>

Error 21 bad method name C:\Users\Женя\Documents\Visual Studio 2008\Projects\Project1\WindowsFormsApplication3\WindowsFormsApplication3\Maybe.cs 60 10 WindowsFormsApplication3

using System;
using System.Collections.Generic;
using System.Linq;

namespace Es.Common.Monads
{
    public class Maybe<T> : IEquatable<Maybe<T>>
    {
        public readonly static Maybe<T> Nothing = new Maybe<T>();
        public T Value { get; private set; }
        public bool HasValue { get; private set; }
        Maybe()
        {
            HasValue = false;
        }
        public Maybe(T value)
        {
            Value = value;
// ReSharper disable RedundantCast
            HasValue = ((object)value != null);
// ReSharper restore RedundantCast
        }

        public bool Equals(Maybe<T> other)
        {
            if (ReferenceEquals(null, other)) return false;
            if (ReferenceEquals(this, other)) return true;
            return Equals(other.Value, Value) && other.HasValue.Equals(HasValue);
        }

        public override bool Equals(object obj)
        {
            if (ReferenceEquals(null, obj)) return false;
            if (ReferenceEquals(this, obj)) return true;
            if (obj.GetType() != typeof (Maybe<T>)) return false;
            return Equals((Maybe<T>) obj);
        }

        public override int GetHashCode()
        {
            unchecked
            {
                return (Value.GetHashCode() * 397) ^ HasValue.GetHashCode();
            }
        }

        public static bool operator ==(Maybe<T> left, Maybe<T> right)
        {
            return Equals(left, right);
        }

        public static bool operator !=(Maybe<T> left, Maybe<T> right)
        {
            return !Equals(left, right);
        }
    }

    public static class MaybeExtentions
    {
        public static Maybe<U> SelectMany<T, U>(
             this Maybe<T> m,
             Func<T, Maybe<U>> k)
        {
            return m.HasValue ? k(m.Value) : Maybe<U>.Nothing;
        }

        public static Maybe<V> SelectMany<T, U, V>(
            this Maybe<T> m,
            Func<T, Maybe<U>> k,
            Func<T, U, V> s)
        {
            return m.SelectMany(x => k(x).SelectMany(y => s(x, y).ToMaybe()));
        }

        public static Maybe<T> ToMaybe<T>(this T value)
        {
            return new Maybe<T>(value);
        }
    }
}

<[ { $x++; $x } ]>

x = ++i;
a = b = c;

AB>эээээ, то есть я правильно понимаю, что компилятор ncc теперь умеет компилировать сразу два языка в зависимости от расширения в рамках одного проекта?

var f = x => x * x;
WriteLine(f(3));

m.SelectMany(x => k(x).SelectMany(y => s(x, y).ToMaybe()));

MaybeExtentions.SelectMany(m, x => MaybeExtentions.SelectMany(k(x), y => MaybeExtentions.ToMaybe(s(x, y))));

H>m.SelectMany(x => k(x).SelectMany(y => s(x, y).ToMaybe()));
H>

using System;
using System.Console;
using System.Linq;

public class Maybe[T]
{
    public static Nothing : Maybe[T] = Maybe();
    public Value : T { get; private set; }
    public HasValue : bool { get; private set; }
}

public module Program
{
    public static SelectMany[T, U](this m : Maybe[T], k : Func[T, Maybe[U]]) : Maybe[U]
    {
        if (m.HasValue) k(m.Value) else Maybe.Nothing;
    }
        
  public static SelectMany[T, U, V](
      this m : Maybe[T],
      k : Func[T, Maybe[U]],
      s : Func[T, U, V]) : Maybe[V]
  {
    m.SelectMany(x => k(x).SelectMany(y => s(x, y).ToMaybe()))
  }

  public static ToMaybe[T](this _value : T) : Maybe[T] { null }

  Main() : void { }
}