In dynamic syntax, you can't pass a struct as a complex argument

[abe545]

You should be able to do this:

public struct Args
{
    // we only check properties... should we check public fields on structs?
    public string Foo { get; set; }
    public int Bar { get; set; }
}

dbConnection.Execute().FooBar(new Args { Foo  = "Hello", Bar = 42 });

However, currently the library will throw an exception stating that the passed argument was not named.