In file included from /in/driver/main.cpp:8:0:
/in/kdtree.hpp: In member function 'KDTree<std::tuple<_Elements ...>, ValueType>::Node* KDTree<std::tuple<_Elements ...>, ValueType>::erase(KDTree<std::tuple<_Elements ...>, ValueType>::Node*, const Key&)':
/in/kdtree.hpp:341:21: error: expected '(' before '{' token
             else if { //(node->left != nullptr) {
                     ^