Cool listcomp
Check this post, which demonstrates the power of Haskell's list comprehensions:
f :: Int -> [ (Int, Int, Int) ] f n = [ (x, y, z) | x <- [ 1 .. n ], y <- [ x+1 .. n ], z <- [ y+1 .. n ], (x * x) + (y * y) == (z * z) ]
I first thought there was some special magic going on, like maybe some Prolog-like matching, but then I realized that you can do the same in Python:
def f(n): return [(x,y,z) for x in range(1, n+1) for y in range(x+1, n+1) for z in range(y+1, n+1) if x*x + y*y == z*z] print f(20)
(Which isn't so surprising after all, as Python "borrowed" list comprehensions from Haskell... but still.)