fix nil pattern matching

src/interpreter.janet

@@ -183,7 +183,7 @@
     :word (match-word pattern value ctx)
 
     # match on equality
-    :nil {:success (nil? value) :ctx ctx}
+    :nil {:success (= :^nil value) :ctx ctx}
     :bool {:success (= data value) :ctx ctx}
     :number {:success (= data value) :ctx ctx}
     :string {:success (= data value) :ctx ctx}

src/ludus.janet

@@ -52,8 +52,7 @@
 (comment
 # (do
 (def source `
-fn id (x) -> x
-map (id, [])
+contains? (:d, [:a, :b])
 `)
 (def out (-> source 
  ludus