diff --git a/lib/parser.js b/lib/parser.js
index f5497fd..8e211f6 100644
--- a/lib/parser.js
+++ b/lib/parser.js
@@ -121,11 +121,18 @@
         descriptions.length = j;
       }
 
-      return descriptions.length > 1
-        ? descriptions.slice(0, -1).join(", ")
-            + " or "
-            + descriptions[descriptions.length - 1]
-        : descriptions[0];
+      switch (descriptions.length) {
+        case 1:
+          return descriptions[0];
+
+        case 2:
+          return descriptions[0] + " or " + descriptions[1];
+
+        default:
+          return descriptions.slice(0, -1).join(", ")
+            + ", or "
+            + descriptions[descriptions.length - 1];
+      }
     }
 
     function describeFound(found) {
@@ -138,9 +145,7 @@
   function peg$parse(input, options) {
     options = options !== void 0 ? options : {};
 
-    var parser = this,
-
-        peg$FAILED = {},
+    var peg$FAILED = {},
 
         peg$startRuleFunctions = { Grammar: peg$parseGrammar },
         peg$startRuleFunction  = peg$parseGrammar,