1 files changed, 10 insertions, 4 deletions

@@ -1,11 +1,17 @@
 --- lam.util
 
-local util = {}
-local unpack = table.unpack or unpack
+local m = {}
 
-function util.pop (tbl)
+function m.pop (tbl)
+        --[[ Remove the first element from TBL. ]]
         return table.remove(tbl, 1)
 end
 
+function m.arity (r, min, max)
+        --[[ Return whether R is within MIN and MAX (inclusive). ]]
+        local len = #r
+        return len >= min and len <= max
+end
+
 ---
-return util
+return m