Extend findmin/findmax functions in CUDA

Currently the findmin/findmax functions in CUDA are defined for cases where one passes in them only a single CuArray (link), e.g. findmin(a). However, findmin/findmax functions in Base allow to pass in them an additional function as the first argument, e.g. findmin(abs2, a).
Would it be hard to extend the existing definitions of CUDA findmin/findmax functions to match the functionality of Base?