3 files changed, 6 insertions, 2 deletions
diff --git a/lexer.cpp b/lexer.cpp
index 46a38bd..3b26c52 100644
--- a/lexer.cpp
+++ b/lexer.cpp
@@ -1,5 +1,7 @@
 #include "lexer.h"
 
+using namespace Lex;
+
 void Tree::clear() {
  nodes.clear();
  root = 0;
diff --git a/lexer.h b/lexer.h
index c571294..c6576d0 100644
--- a/lexer.h
+++ b/lexer.h
@@ -3,6 +3,8 @@
 #include "minicc.h"
 #include "bnf.h"
 
+namespace Lex {
+
 struct TreeNode {
  index_t parent{};
  std::vector<index_t> childs; // fill char by char
@@ -53,4 +55,4 @@ public:
 
 };
 
-
+} // namespace Lex
diff --git a/test-lexer.cpp b/test-lexer.cpp
index 39db3ec..b76f4cc 100644
--- a/test-lexer.cpp
+++ b/test-lexer.cpp
@@ -76,7 +76,7 @@ TEST_F(Test, BNF) {
   {"identifier", "XYZ", { 1, 34}},
  };
 
- Lexer lexer(LexBNF, LexTop);
+ Lex::Lexer lexer(LexBNF, LexTop);
  auto tokens = lexer.Lex(Code);
 
  ASSERT_EQ(tokens, tokens_reference);