Is there any use for unique_ptr with array?

c++ c++11 smart-pointers unique-ptr
fen picture fen · May 23, 2013 · Viewed 162.9k times · Source

std::unique_ptr has support for arrays, for instance:

std::unique_ptr<int[]> p(new int[10]);

but is it needed? probably it is more convenient to use std::vector or std::array.

Do you find any use for that construct?

Answer

Nicol Bolas picture Nicol Bolas · May 23, 2013

Some people do not have the luxury of using std::vector, even with allocators. Some people need a dynamically sized array, so std::array is out. And some people get their arrays from other code that is known to return an array; and that code isn't going to be rewritten to return a vector or something.

By allowing unique_ptr<T[]>, you service those needs.

In short, you use unique_ptr<T[]> when you need to. When the alternatives simply aren't going to work for you. It's a tool of last resort.

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