src/cpp-common/vector.hpp

   1 #ifndef SRC_CPP_COMMON_VECTOR_HPP
   2 #define SRC_CPP_COMMON_VECTOR_HPP
   3
   4 #include <vector>
   5 #include "common/assert.h"
   6
   7 namespace bt2_common {
   8
   9 /*
  10  * Moves the last entry of `vec` to the index `idx`, then removes the last entry.
  11  *
  12  * Meant to be a direct replacement for g_ptr_array_remove_index_fast(), but for
  13  * `std::vector`.
  14  */
  15 template <typename T, typename AllocatorT>
  16 void vectorFastRemove(std::vector<T, AllocatorT>& vec,
  17                       const typename std::vector<T, AllocatorT>::size_type idx)
  18 {
  19     BT_ASSERT_DBG(idx < vec.size());
  20
  21     if (idx < vec.size() - 1) {
  22         vec[idx] = std::move(vec.back());
  23     }
  24
  25     vec.pop_back();
  26 }
  27
  28 } /* namespace bt2_common */
  29
  30 #endif /* SRC_CPP_COMMON_VECTOR_HPP */