fix pos in syntax error exception

lib/parse.js

@@ -181,7 +181,7 @@ function JS_Parse_Error(message, line, col, pos) {
     this.message = message;
     this.line = line;
     this.col = col;
-    this.pos = pos + 1;
+    this.pos = pos;
     this.stack = new Error().stack;
 };