[Haskell-beginners] \x -> x < 0.5 && x > -0.5

[Isaac Dupree]

Michael Mossey wrote:
> Eliminating variables and working with function combinations has 
> benefits. The one suggestion I've seen here that seems to be right on 
> the money is
> 
> liftM2 (&&) (< 0.5) (> -0.5)

yep, I might not write it myself, but it's definitely the only one 
straightforward enough to perhaps justify itself.

now for a completely different suggestion; you write

> filter (\x -> x < 0.5 && x > -0.5) xs

but as a reader I would find it clearer to switch the order to numerical:
filter (\x -> x > -0.5 && x < 0.5) xs

(in this particular instance, we can observe numerical properties and 
even change to (\x -> abs x < 0.5) if we so desire.  Which can be 
written point-free as ((< 0.5) . abs), if you want to.)

-Isaac