Numerals in Positional Notation   [4]

ip  = sum . map (uncurry (*))

numl b = ip . zip pows . reverse . map val
         where pows = iterate (b*) 1

ip  = sum . map (uncurry (*))

-- Consolidate points-free definitions in-line

numl b = sum . map (uncurry (*)) . zip (iterate (b*) 1) . 
         reverse . map val

-- Consolidation enables simplification

numl b = sum . zipWith (*) (iterate (b*) 1) . 
         reverse . map val