ArgBuilder which provides a value for a keyword argument. The KeywordArgBuilder calculates its position at emit time using it's initial offset within the keyword arguments, the number of keyword arguments, and the total number of arguments provided by the user. It then delegates to an underlying ArgBuilder which only receives the single correct argument. Delaying the calculation of the position to emit time allows the method binding to be done without knowing the exact the number of arguments provided by the user. Hence, the method binder can be dependent only on the set of method overloads and keyword names, but not the user arguments. While the number of user arguments could be determined upfront, the current MethodBinder does not have this design.