How to use conditional operator inside Math.max() method CoffeeScript

I wanna ask for the best practice in CoffeeScript

JavaScript:

k = Math.max(n >= 0 ? n : len - Math.abs(n), 0)

I was looking for sth like k = Math.max if n >= 0 then n else len - Math.abs(n), 0 but this returns error "unexpected , "

CoffeeScript:

v = if n >= 0 then n else len - Math.abs(n)
k = Math.max v, 0

Is any better way to use condition inside max() method?