1 files changed, 2 insertions, 0 deletions

diff --git a/lib/fields.cc b/lib/fields.cc
index d494098..91fbc41 100644
--- a/lib/fields.cc
+++ b/lib/fields.cc
@@ -1,29 +1,31 @@
 #include <opkele/types.h>
 #include <opkele/exception.h>
 #include <opkele/util.h>
+#include <algorithm>
 
 namespace opkele {
+    using std::for_each;
     using std::unary_function;
 
     struct __om_copier : public unary_function<const string&,void> {
         public:
             const basic_fields& from;
             basic_fields& to;
 
             __om_copier(basic_fields& t,const basic_fields& f)
                 : from(f), to(t) { }
 
             result_type operator()(argument_type f) {
                 to.set_field(f,from.get_field(f)); }
     };
 
     basic_fields::basic_fields(const basic_fields& x) {
         x.copy_to(*this);
     }
     void basic_fields::copy_to(basic_fields& x) const {
         x.reset_fields();
         for_each(fields_begin(),fields_end(),
                 __om_copier(x,*this) );
     }
     void basic_fields::append_to(basic_fields& x) const {
         for_each(fields_begin(),fields_end(),