split off the position information

src/main/resources/org/sablecc/sablecc/parser.txt

@@ -382,7 +382,7 @@ Macro:ParserParseTail
                     }
                 case ERROR:
                     throw new ParserException(this.last_token,
-                        "[" + this.last_line + "," + this.last_pos + "] " +
+                        "[" + this.last_line + "," + this.last_pos + "] " ,
                         Parser.errorMessages[Parser.errors[this.action[1]]]);
             }
         }
@@ -673,6 +673,7 @@ import $1$.*;
 public class ParserException extends Exception
 {
     Token token;
+    String realMsg;
 
     public ParserException(  Token token, String  message)
     {
@@ -680,10 +681,22 @@ public class ParserException extends Exception
         this.token = token;
     }
 
+    public ParserException(  Token token, String prefix, String  message)
+    {
+        super(prefix+message);
+        this.realMsg = message;
+        this.token = token;
+    }
+
     public Token getToken()
     {
         return this.token;
     }
+
+    public Token getRealMsg()
+    {
+        return this.realMsg;
+    }
 }
 
 $