Add functionality that allows the set macro to

take a tuple as an l-value. Remove the old
multi-sym report in anticipation of a different
mechanism.

examples/3sum.janet

@@ -5,10 +5,10 @@
   (def solutions @{})
   (def len (length s))
   (for k 0 len
-    (put tab s.k k))
+    (put tab (s k) k))
   (for i 0 len
     (for j 0 len
-      (def k (get tab (- 0 s.i s.j)))
+      (def k (get tab (- 0 (s i) (s j))))
       (when (and k (not= k i) (not= k j) (not= i j))
         (put solutions {i true j true k true} true))))
   (map keys (keys solutions)))