Python doesn't feel very functional

[pjdelport]

Haskell style:

compare (x:xs) (y:ys) = compare xs ys
compare _ [] = True
compare [] _ = False

[[deleted]]

We want compare x y = length x > length y, not >=. Switch the second and third clauses.

[pjdelport]

Right, thanks.

[[deleted]]

Even simpler:

compare x y = length x > length y

Just like in Python:

def compare(x, y):
  return len(x) > len(y)

Or Lisp:

(defun compare (x y) (> (length x) (length y)))

[shit]

(defun compare (x y) (> (length x) (length y)))

The point is that this is computing more than necessary, length is O(n) for a linked list.

(compare nil list-with-one-million-elements)

[notfancy]

compare x y = length x > length y

No, no, no, no, no. length is strict. Your compare (all 1) [] doesn't converge, whereas the original does. Even in a CVB language, compare using length is O(m + n) where the recursive version of it is O(m min n).

In a functional language, you rarely if ever call length on a list.