diff --git a/lib/compiler/passes/generate-js.js b/lib/compiler/passes/generate-js.js
index 089970c..1a4a278 100644
--- a/lib/compiler/passes/generate-js.js
+++ b/lib/compiler/passes/generate-js.js
@@ -1450,7 +1450,7 @@ function generateJS( ast, session, options ) {
             "    }",
             "  }",
             "",
-            use( "filename" ) ? " var peg$VALIDFILENAME = typeof options.filename === \"string\" && options.filename.length > 0;" : "",
+            use( "filename" ) ? "  var peg$VALIDFILENAME = typeof options.filename === \"string\" && options.filename.length > 0;" : "",
             "  function peg$computeLocation(startPos, endPos) {",
             "    var loc = {};",
             "",
diff --git a/lib/parser.js b/lib/parser.js
index 7677c3f..0ebc7fb 100644
--- a/lib/parser.js
+++ b/lib/parser.js
@@ -448,7 +448,7 @@ function peg$parse(input, options) {
     }
   }
 
- var peg$VALIDFILENAME = typeof options.filename === "string" && options.filename.length > 0;
+  var peg$VALIDFILENAME = typeof options.filename === "string" && options.filename.length > 0;
   function peg$computeLocation(startPos, endPos) {
     var loc = {};