adam@11: fun numFields [r ::: {Type}] (fl : folder r) (r : $r) : int =
adam@11:     @fold [fn _ => int] (fn [nm ::_] [u ::_] [r ::_] [[nm] ~ r] acc => acc+1) 0 fl
adam@11: 
adam@10: fun mem [a ::: Type] [ns ::: {Unit}] (_ : eq a) (fl : folder ns) (x : a) (r : $(mapU a ns)) : bool =
adam@10:     @foldUR [a] [fn _ => bool]
adam@10:      (fn [nm ::_] [r ::_] [[nm] ~ r] y acc =>
adam@10:          acc || x = y)
adam@10:      False fl r
adam@12: 
adam@12: fun equal [ts ::: {Type}] (eqs : $(map eq ts)) (fl : folder ts) (r1 : $ts) (r2 : $ts) : bool =
adam@18:     @foldR3 [eq] [ident] [ident] [fn _ => bool]
adam@12:      (fn [nm ::_] [t ::_] [r ::_] [[nm] ~ r] isEq x y acc =>
adam@12:          acc && @eq isEq x y)
adam@12:      True fl eqs r1 r2