How would you write this Clojure snippet in Ruby and/or Haskell?
- by dnolen
I was working on a Rails template and was trying to write a bit of code that allows me to populate a table or multiple columns of ul tags "top-to-bottom" and "left-to-right" across however many columns I specify. I'm just getting the hang of Ruby so I couldn't figure this out. I'm also curious about an idiomatic Haskell version for this useful snippet. Improvements to Clojure version appreciated:
(defn table [xs & {:keys [cols direction]
:or {cols 1 direction 'right}}]
(into []
(condp = direction
'down (let [c (count xs)
q (int (/ c cols))
n (if (> (mod c q) 0) (inc q) q)]
(apply map vector (partition n n (repeat nil) xs)))
'right (map vec (partition cols cols (repeat nil) xs)))))
With this bit of code I can then do the following:
(table (range 10) :cols 3)
Printed out this would look like so:
0 1 2
3 4 5
6 7 8
9
And the trickier one:
(table (range 10) :cols 3 :direction 'down)
Looks like so:
0 4 8
1 5 9
2 6
3 7
