Currently, list hooks do not declare a move constructor. When moved, the copy constructor is called instead, resulting the moved-from hook still linked and the moved-to hook unlinked (https://godbolt.org/z/zKqqhbxz5). An consequence is that objects containing list hooks cannot be safely put inside some STL containers like std::vector (https://godbolt.org/z/vq765G5n5). Furthermore, it is not alway possible to implement a desired move constructor for the class containing list hooks, since link / unlink cannot be performed without the list object if the list has constant time size().
I think making the following changes to list hooks would make them safer and more broadly useful:
- declare the move constructor as deleted
- enabled with an option, add a move constructor that unlinks the moved-from hook and link the moved-to hook in its place
Currently, list hooks do not declare a move constructor. When moved, the copy constructor is called instead, resulting the moved-from hook still linked and the moved-to hook unlinked (https://godbolt.org/z/zKqqhbxz5). An consequence is that objects containing list hooks cannot be safely put inside some STL containers like
std::vector(https://godbolt.org/z/vq765G5n5). Furthermore, it is not alway possible to implement a desired move constructor for the class containing list hooks, since link / unlink cannot be performed without the list object if the list has constant timesize().I think making the following changes to list hooks would make them safer and more broadly useful: