lex: Added return code

Author: pbeckingham

src/lex.cpp

@@ -15,6 +15,8 @@ int main (int argc, char** argv)
     while (l.token (token, type))
       std::cout << "  token '" << token << "' " << Lexer::typeToString (type) << "\n";
   }
+
+  return 0;
 }
 
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