std::array+alternatives #RAII dtor

feature wish list — RAII; fixed size; bound check compares vector ^ unique_ptr ^ std::array. Conclusion — Vector is more powerful, more versatile, more widely useful, less restrictive. std::array is

All alternatives to std::array:

  • vector and raw array
  • boost::scoped_array and boost::shared_array — least quizzed.
  • std::unique_ptr<int[]> dynArr(new int[theSize]) # can be allocated on heap at runtime, and you don’t need to call delete[]

The dtor in each data structure is a key feature if you want RAII:

  1. std::array — dtor probably destroys each element one by one. No q(delete) called since the elements could be on stack
  2. scoped_array — dtor calls delete[], which is a key difference from scoped_ptr, according to my book [[beyond the c++ standard lib]]
  3. vector — dtor uses its allocator, which very likely calls delete[] since vector uses heap for the underlying growable array.
  4. unique_ptr<T[]> — yes as expected. This valgrind experiment shows the array-specialization uses delete[], whereas the vanilla instance uses regular q(delete).

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