First pass at a scheme backend

src/Data/SnocList.newt

@@ -9,6 +9,13 @@ snoclen {a} xs = go xs Z
     go Lin acc = acc
     go (xs :< x) acc = go xs (S acc)
 
+snoclen' : ∀ a. SnocList a → Int
+snoclen' {a} xs = go xs 0
+  where
+    go : SnocList a → Int → Int
+    go Lin acc = acc
+    go (xs :< x) acc = go xs (1 + acc)
+
 snocelem : ∀ a. {{Eq a}} → a → SnocList a → Bool
 snocelem a Lin = False
 snocelem a (xs :< x) = if a == x then True else snocelem a xs