Split Function Arg Conventions
sf_args(trim, label, first)logical(1). Should splits corresponding with 0 observations be kept when tabulating.
character(1). A label (not to be confused with the name) for the object/structure.
logical(1). Should the created split level be placed first in the levels (TRUE) or last (FALSE, the default).
NULL (this is an argument template dummy function)
Other conventions:
compat_args(),
constr_args(),
gen_args(),
lyt_args()