>Thx - very interesting to see that they varied the algorithm depending on the context
>Nice to know I was right (although I admit that after considering your initial post I thought I was wrong ) :-}

Well, my initial post made sense to me as well - just did not consider the compiler trickery

In the case of integers, it works as I thought (there's no Concat there)

I cannot think of a good reference type that implements the operator +, so I cannot check.

Did a check with the reference type delegate

Interesting- aside from the fact that it calls delegate.Combine() 3 times -

Each time a method is used ( xx, yy, zz) to add to the delegate, it loads the reference to the function, calls a delegate constructor with the function as a parameter, and then calls Combine which accepts two delegates.

When I look at the signatures of Delegate.Combine http://msdn.microsoft.com/en-us/library/b1eh4771.aspx there is also Delegate.Combine( Delegate[]) and it does not use that

	delegate void TheDelegate ( int i );
	class Program
	{




		static void xx(int i)
		{
		}

		static void yy(int i)
		{
		}

		static void zz(int i)
		{
		}
		static void Main(string[] args)
		{

			TheDelegate chain = null ;
			chain = chain + xx + yy + zz;


			return;
		}
	}

listing

.method private hidebysig static void  Main(string[] args) cil managed
{
  .entrypoint
  // Code size       74 (0x4a)
  .maxstack  4
  .locals init ([0] class CoreTest.TheDelegate chain)
  IL_0000:  nop
  IL_0001:  ldnull
  IL_0002:  stloc.0
  IL_0003:  ldloc.0
  IL_0004:  ldnull
  IL_0005:  ldftn      void CoreTest.Program::xx(int32)
  IL_000b:  newobj     instance void CoreTest.TheDelegate::.ctor(object,
                                                                 native int)
  IL_0010:  call       class [mscorlib]System.Delegate [mscorlib]System.Delegate::Combine(class [mscorlib]System.Delegate,
                                                                                          class [mscorlib]System.Delegate)
  IL_0015:  castclass  CoreTest.TheDelegate
  IL_001a:  ldnull
  IL_001b:  ldftn      void CoreTest.Program::yy(int32)
  IL_0021:  newobj     instance void CoreTest.TheDelegate::.ctor(object,
                                                                 native int)
  IL_0026:  call       class [mscorlib]System.Delegate [mscorlib]System.Delegate::Combine(class [mscorlib]System.Delegate,
                                                                                          class [mscorlib]System.Delegate)
  IL_002b:  castclass  CoreTest.TheDelegate
  IL_0030:  ldnull
  IL_0031:  ldftn      void CoreTest.Program::zz(int32)
  IL_0037:  newobj     instance void CoreTest.TheDelegate::.ctor(object,
                                                                 native int)
  IL_003c:  call       class [mscorlib]System.Delegate [mscorlib]System.Delegate::Combine(class [mscorlib]System.Delegate,
                                                                                          class [mscorlib]System.Delegate)
  IL_0041:  castclass  CoreTest.TheDelegate
  IL_0046:  stloc.0
  IL_0047:  br.s       IL_0049
  IL_0049:  ret
} // end of method Program::Main