1 files changed, 7 insertions, 2 deletions
diff --git a/extractor/grammar_extractor.h b/extractor/grammar_extractor.h
index f50a8d14..6b1dcf98 100644
--- a/extractor/grammar_extractor.h
+++ b/extractor/grammar_extractor.h
@@ -1,18 +1,21 @@
 #ifndef _GRAMMAR_EXTRACTOR_H_
 #define _GRAMMAR_EXTRACTOR_H_
 
+#include <memory>
 #include <string>
 #include <vector>
 
-#include "rule_factory.h"
-
 using namespace std;
 
+namespace extractor {
+
 class Alignment;
 class DataArray;
 class Grammar;
+class HieroCachingRuleFactory;
 class Precomputation;
 class Rule;
+class Scorer;
 class SuffixArray;
 class Vocabulary;
 
@@ -46,4 +49,6 @@ class GrammarExtractor {
   shared_ptr<HieroCachingRuleFactory> rule_factory;
 };
 
+} // namespace extractor
+
 #endif