diff --git a/lexer.js b/lexer.js
index 0606cdcac..a59ff7689 100644
--- a/lexer.js
+++ b/lexer.js
@@ -54,7 +54,7 @@ Lexer.prototype.lex = function() {
         }
     }
 
-    throw "Unexpected character: '" + toMatch[0] + "' at position " + this._pos;
+    throw "Unexpected character: '" + this._input[0] + "' at position " + this._pos;
 };
 
 Lexer.prototype.setInput = function(input) {