Minimum size implementation for bool array

Question

I need a minimum size implementation of an array of bools. The size of the array is known at compile time.

I checked std::bitset and boost::array, but they both incur an overhead that is significant for small arrays. For example, if the array size is 8, the container should only use 1 byte of memory (assuming common CPU architecture).

Does this exist or do I need to roll my own?

Answer 1

You can make it by your own, but not from scratch. bitset implementation should have a couple of lines looking like typedef unsigned long _WordT; (SGI) or typedef _Uint32t _Ty; (MSVS). You could carefully replace the type and namespace and make your own container this way. I changed the type to char and sizeof returns 1 (vs2010 proof-of-concept on pastebin)