[boost] Re: Review Request: cyclic_buffer

From: Alisdair Meredith (alisdair.meredith_at_[hidden])
Date: 2003-06-10 11:54:13

Nigel Stewart wrote:

>         To summarise:
> 
>         Possible resize policies:
> 
>         i.      Capacity is fixed at compile time.
>         ii.     Capacity is fixed at construction time.
>         iii.    Capacity can be manually managed by client code.
>         iv.     Capacity is allowed to grow automatically. (ala std::vector)
> 
>         Possible insert handling policies:
> 
>         I.      Insert into full buffer results in no change.
>         II.     Insert into full buffer results in overwriting opposite end.
>                 Insertion into arbitrary position overwrites beginning, if necessary.
>         III.    Insert into full buffer results in exception.
> 
>         Possible resize to smaller capacity policies:
> 
>         1.      Keep left-most items. (ala std::vector)
>         2.      Keep right-most items.
> 
>         The general gist of some random googling on "circular buffers":
> 
>         - Automatic resizing does not appear to be common.
>         - No established convention in relation to arbitrary insert.
>         - No established convention in relation to resizing to smaller capacity.

Another distinction might be 'black box / white box', i.e. whether you
have public access to the iterators.  If you are merely using a fixed,
circular buffer to stop your queue/stack reallocating, you may want to
hide them.  

This is a relatively minor detail.  Something I would address in a
policy-based implementation, but not in the 'best generalisation for
common cases'.

-- 
AlisdairM