case TrackChain::UNSPECIFIED: conv.result("UNSPECIFIED"); return;
case TrackChain::UP: conv.result("UP"); return;
case TrackChain::DOWN: conv.result("DOWN"); return;
- default: throw lexical_error(format("conversion of Direction(%d) to string", dir));
+ default: throw lexical_error(format("conversion of Direction(%d) to string", static_cast<int>(dir)));
}
}