// 'Identity' is a lambda that accepts an argument of any type and
 // returns the value of its parameter.  
auto Identity = [](auto a) { return a; };
int three = Identity(3);
char const* hello = Identity("hello");

static class Foo
{
  public T Identity<T>(T x) { return x; }
}

А> // 'Identity' is a lambda that accepts an argument of any type and
А> // returns the value of its parameter.  
А>auto Identity = [](auto a) { return a; };
А>int three = Identity(3);
А>char const* hello = Identity("hello");
А>

def Identity[T](a) { a }
def three = Identity(3);
def hello = Identity("hello");

А>> // 'Identity' is a lambda that accepts an argument of any type and
А>> // returns the value of its parameter.  
А>>auto Identity = [](auto a) { return a; };
А>>int three = Identity(3);
А>>char const* hello = Identity("hello");
А>>

DR>def Identity[T](a) { a }
DR>def three = Identity(3);
DR>def hello = Identity("hello");
DR>

  Main() : void
  {
  def Identity[T](a) { a }
def three = Identity(3);
def hello = Identity("hello");

      WriteLine($"$three $hello");
    _ = ReadLine();
  }

_NN>>Не подскажете какой компилятор С++ 11 это дело умеет компилировать ?

g++ --version

g++ (rev2, Built by MinGW-builds project) 4.8.0
Copyright (C) 2013 Free Software Foundation, Inc.

g++ --std=c++11 a.cpp

a.cpp: In function 'int main()':
a.cpp:2:17: error: parameter declared 'auto'
  auto x=[](auto a){return a;};
                 ^
a.cpp: In lambda function:
a.cpp:2:27: error: 'a' was not declared in this scope
  auto x=[](auto a){return a;};

DR>def Identity[T](a) { a }
DR>def three = Identity(3);
DR>def hello = Identity("hello");
DR>

def Identity[T](a : T) { a }

macro Identity(a, b)
{
  <[ $a + $b ]>
}

namespace A
{
  macro Identity(a, b)
  {
    <[ $a + $b ]>
  }
}

using A;

def three = Identity(3,1);
def hello = Identity(3.1,2);

System.Console.WriteLine(hello);

ncc a.n -t dll -r Nemerle.Compiler.dll -o a.dll
ncc b.n -t exe -r a.dll -o b.exe

b.exe
5.1

kvar[T]
{
  x,y,z,t:T;
}

macro mul(a,b:T){T(a.x*b.x+a.y*b.y+a.z*b.z-a.t*b.t,.....,.....,.....)}

using Nemerle.Compiler;
using Nemerle.Compiler.Parsetree;

macro cross(t, u, v)
{
    <[
        def u = $u;
        def v = $v;
        $t
            ( u.y * v.z - u.z * v.y
            , u.z * v.x - u.x * v.z
            , u.x * v.y - u.y * v.x
            )
    ]>
}

[ Record ]
class V3
{
    public x : double;
    public y : double;
    public z : double;

    public override ToString() : string
    {
        $"[$x $y $z]"
    }
}

System.Console.WriteLine(cross(V3, V3(1,2,3), V3(4,5,6)));

[-3 6 -3]

// Test
public static void Main()
{
    V3 v = new V3((double)1, (double)2, (double)3);
    V3 v2 = new V3((double)4, (double)5, (double)6);
    Console.WriteLine(new V3(v.y * v2.z - v.z * v2.y, v.z * v2.x - v.x * v2.z, v.x * v2.y - v.y * v2.x));
}