I'm not sure how to move this forward. I left the old API untouched to enable an easier migration path. The methods are not necessary any more. OTOH, they can be useful in some cases (see the motivation for ~:). I'd prefer a more general solution to the tuple problem in Scala itself (using HList types so you can abstract over arity and provide all these operations in a unified way) and then deprecate and remove TupleMethods in Slick.