diff --git a/lib/parse.js b/lib/parse.js
index 6d69461c..3ccdec80 100644
--- a/lib/parse.js
+++ b/lib/parse.js
@@ -579,10 +579,10 @@ var UNARY_POSTFIX = makePredicate([ "--", "++" ]);
 var ASSIGNMENT = makePredicate([ "=", "+=", "-=", "/=", "*=", "%=", ">>=", "<<=", ">>>=", "|=", "^=", "&=" ]);
 
 var PRECEDENCE = (function(a, ret){
-    for (var i = 0, n = 1; i < a.length; ++i, ++n) {
+    for (var i = 0; i < a.length; ++i) {
         var b = a[i];
         for (var j = 0; j < b.length; ++j) {
-            ret[b[j]] = n;
+            ret[b[j]] = i + 1;
         }
     }
     return ret;