How is the upcoming 'dynamic' keyword in .net 4.0 going to make my life better?

Question

I don\'t quite get what it\'s going to let me do (or get away with :)

Answer 1

The two big areas are:

• working with COM assemblies where methods return vague types - so you can essentially use late binding
• working with DLR types

Other uses include things like:

• duck-typing where there is no interface
• Silverlight talking to the host page's DOM
• talking to an xml file.

In C# itself, this allows a few things, such as a basic approach to generic operators:

static T Add(T arg1, T arg2) { // doesn't work in CTP
     return ((dynamic)arg1) + ((dynamic)arg2);
}

(of course, I'd argue that this is a better (more efficient) answer to this)