Merge branch 'main' of github.com:braxtonhall/fib

1 files changed, 18 insertions, 0 deletions

diff --git a/entries/zgrannan/Fib.hs b/entries/zgrannan/Fib.hs
new file mode 100644
index 0000000..1918fc8
--- /dev/null
+++ b/entries/zgrannan/Fib.hs
@@ -0,0 +1,18 @@
+-- Point-less fibonacci
+fib :: Int -> Int
+fib = fix fib'
+  where
+    fib' =
+      ap (when 0 . (0 ==)) .
+      ap (when 1 . (1 ==)) .
+      ap (ap . ((+) .) . (. subtract 1)) (. subtract 2)
+
+    when t c e = if c then t else e
+
+    ap mf m = mf >>= (\f -> m >>= return . f)
+
+    fix f  = f (fix f)
+
+
+main :: IO ()
+main = mapM_ (print . fib) [0 .. 10]