LookImUsingRuby.cs

using System;
using System.Dynamic;

class LookImUsingRuby
{
    static void Main(string[] args)
    {
        var x = new { Foo = 1, Bar = "data" }; // anonymous object!

        Console.WriteLine(x.Foo); // this is type-checked because within this method, we know Foo exists
        PrintFoo(x); // no typechecking beyond this point. it works, though

        dynamic y = new ExpandoObject(); // this one doesn't even have a preset structure lol
        y.Foo = "???"; // a different type to x.Foo
        PrintFoo(y); // and yet this still works
    }

    static void PrintFoo(dynamic x)
    {
        Console.WriteLine(x.Foo);
    }
}