diff --git a/src/lp/detail/field-decl.hpp b/src/lp/detail/field-decl.hpp
index 0738768..6804b8a 100644
--- a/src/lp/detail/field-decl.hpp
+++ b/src/lp/detail/field-decl.hpp
@@ -44,7 +44,7 @@
   decode(const Block& wire)
   {
     if (wire.type() != TlvType::value) {
-      BOOST_THROW_EXCEPTION(ndn::tlv::Error("Unexpected TLV type " + std::to_string(wire.type())));
+      BOOST_THROW_EXCEPTION(ndn::tlv::Error("Unexpected TLV type " + to_string(wire.type())));
     }
 
     T type;
@@ -60,7 +60,7 @@
   decode(const Block& wire)
   {
     if (wire.type() != TlvType::value) {
-      BOOST_THROW_EXCEPTION(ndn::tlv::Error("Unexpected TLV type " + std::to_string(wire.type())));
+      BOOST_THROW_EXCEPTION(ndn::tlv::Error("Unexpected TLV type " + to_string(wire.type())));
     }
 
     return readNonNegativeInteger(wire);
@@ -74,11 +74,11 @@
   decode(const Block& wire)
   {
     if (wire.type() != TlvType::value) {
-      BOOST_THROW_EXCEPTION(ndn::tlv::Error("Unexpected TLV type " + std::to_string(wire.type())));
+      BOOST_THROW_EXCEPTION(ndn::tlv::Error("Unexpected TLV type " + to_string(wire.type())));
     }
 
     if (wire.value_size() == 0) {
-      BOOST_THROW_EXCEPTION(ndn::tlv::Error(std::to_string(wire.type()) + " must not be empty"));
+      BOOST_THROW_EXCEPTION(ndn::tlv::Error(to_string(wire.type()) + " must not be empty"));
     }
 
     return std::make_pair(wire.value_begin(), wire.value_end());