C++26 inplace_vector

[nebkat]

Channel

C++Weekly

Topics

<inplace_vector> has just been accepted for C++26!

• What is it?
  • "A dynamically-resizable vector with fixed capacity and embedded storage"
• Why is it useful (generally)?
  • Embedded
  • Avoiding allocation
  • Non-default constructible objects (vs. std::array)
• What does it replace?
  • std::array + "size"
  • Returning variable length results from functions, without having to allocate
• Available implementations?
  • Reference implementation provided by paper godbolt.
  • Until added to compilers, available as boost::container::static_vector.
  • Potentially expand to cover other containers available in boost::container such as small_vector?

Length

Bite-sized (5-10 minutes)

[fcolecumberri]

This is the kind of stuff one would wrongly assume C++ would take less than 40 years to implement. /hj