Getting the argument names along with values in a dynamic method invoke

Question

I am implementing a DynamicObject. In the TryInvokeMethod, in addition to the arguments ( passed in to the method), I also need the names for the parameters if they have been used.

I can see that binder.CallInfo.ArgumentNames does indeed provides the names, but I am not able to associate them with the values. Is there any way to do so, or am I hoping against hope:

public override bool TryInvokeMember(InvokeMemberBinder binder, object[] args, out object result)
{
    var names = binder.CallInfo.ArgumentNames;
    foreach (var arg in args)
    {
        arguments.Add(new Argument(arg));
    }
    //I need to associate the names and the args
    result = this;
    return true;
}

So for example if I do a call like:

myDynamicObject.DynamicInvoke("test", something: "test2")

I have test and test2, and also something, but I am not able to get the information that something was the name for test2 and test had no name.

Answer 1

I had to use the fact that named arguments occur only after the non-named ones are specified ( thanks to user629926 for pointing to the obvious) and initial code:

var names = binder.CallInfo.ArgumentNames;
var numberOfArguments = binder.CallInfo.ArgumentCount;
var numberOfNames = names.Count;

var allNames = Enumerable.Repeat<string>(null, numberOfArguments - numberOfNames).Concat(names);
arguments.AddRange(allNames.Zip(args, (flag, value) => new Argument(flag, value)));