Pavel Vozenilek wrote:
"Ion Gaztañaga" wrote:
std::list::size":
One solution may be to provide list::size() and have the size itself encoded as a signed integer. If the integer is >= 0 then the size() will return it.
After splice() the number will be set negative. Only the next size() call will go through the list and set the correct value again. For a typical list<> use the size() should get amortized to O(1).
Alexandrescu had discussed this few years ago in context of his YASLI library.
This can be an option. The downside is that size() is a const function and we should declare the size member as mutable. This converts a thread-safe function like size() to a non-thread safe one. But I agree that this can be a good solution. To avoid wasting a bit of the internal size integer, we could define size() as "this->size_ - 1", so this->size_ == 0 could represent unknown size and this->size_== 1 an empty list, this->size_ == 2 a list with just 1 element and so on. Regards, Ion