Rationale

The basic motivation behind the circular_buffer was to create a container which would work seamlessly with STL.

Additionally, the design of the circular_buffer was guided by the following principles:

Maximum efficiency for envisaged applications.
Suitable for general purpose use.
The behaviour of the buffer as intuitive as possible.
Suitable for specialization by means of adaptors. (The circular_buffer_space_optimized is such an example of the adaptor.)
Easy to debug. (See Debug Support for details.)

In order to achieve maximum efficiency, the circular_buffer and circular_buffer_space_optimized store their elements in a contiguous region of memory, which then enables:

Possible applications of the circular buffer include:

Storage of the most recently received samples, overwriting the oldest as new samples arrive.
As an underlying container for a bounded buffer (see the Bounded Buffer example, code at circular_buffer_bound_example.cpp).
A kind of cache storing a specified number of last inserted elements.
Efficient fixed capacity FIFO (First In, First Out),
Efficient fixed capacity LIFO (Last In, First Out) queue which removes the oldest (inserted as first) elements when full.

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