const Data& operator[](const String& key) const {
if (isHash()) {
const auto it = hash_.find(key);
if (it == hash_.end()) {
return kNilData;
}
return it->second;
} else if (isDrop()) {
return (*drop_)[key];
} else {
throw std::runtime_error("[] requires a hash or drop");
}
}
PieceType pieceTypeFromOrDropped() const { return (isDrop() ? pieceTypeDropped() : pieceTypeFrom()); }
std::shared_ptr<Drop> drop() const {
if (!isDrop()) {
throw std::runtime_error("drop() requires a drop");
}
return drop_;
}
// 移動した後の駒の種類
PieceType pieceTypeTo() const {
if(isDrop()) {
return pieceTypeDropped();
}
return pieceTypeTo(pieceTypeFrom());
}