diff --git a/lib/compiler.js b/lib/compiler.js
index eb73fd0..511e56a 100644
--- a/lib/compiler.js
+++ b/lib/compiler.js
@@ -394,8 +394,8 @@ PEG.Grammar.Rule.prototype.compile = function() {
 
   return PEG.Compiler.formatCode(
     "result._parse_${name} = function(context) {",
-    "  this._cache[${name|string}] = this._cache[${name|string}] || [];",
-    "  var cachedResult = this._cache[${name|string}][this._pos];",
+    "  var cacheKey = ${name|string} + '@' + this._pos;",
+    "  var cachedResult = this._cache[cacheKey];",
     "  if (cachedResult !== undefined) {",
     "    this._pos = cachedResult.nextPos;",
     "    return cachedResult.result;",
@@ -408,7 +408,7 @@ PEG.Grammar.Rule.prototype.compile = function() {
     "  ${restoreReportMatchFailuresCode}",
     "  ${reportMatchFailureCode}",
     "  ",
-    "  this._cache[${name|string}][pos] = {",
+    "  this._cache[cacheKey] = {",
     "    nextPos: this._pos,",
     "    result:  ${resultVar}",
     "  };",