On Thu, 25 Nov 2021 at 08:52, Matt Bentley via SG14 <sg14_at_[hidden]>
wrote:

> Hi Paul,
> it'd throw because returning a value matching an inaccurate input value
> might lead to the user expecting that they could reasonably manually
> specify a min/max block capacity in colony/hive that they can't.


Would it not be a bug for the user to try to do that?


> But
> you're right it should be const.
> I don't think it's unreasonable to add it now, it's basically a 5-line
> function, my main question is whether or not people would find it useful.
>
>
> On 25/11/2021 9:11 pm, Paul M. Bendixen wrote:
> > Hi
> > I'm curious as to why you would want to have a function that is only
> > inspecting a container throw? (and not be const).
> > I can follow your reasoning why you would want it, but is it something
> > that could be added later without breaking ABI (which seems to be the
> > most important thing in the world right now)?
> > If so, maybe it could be another paper that would perhaps be easier to
> > get in on its own.
> >
> > Best
> > Paul
> >
> > tor. 25. nov. 2021 02.35 skrev Matt Bentley via SG14
> > <sg14_at_[hidden] <mailto:sg14_at_[hidden]>>:
> >
> > Hi all,
> > thinking about including a
> > size_type sizeof_block_metadata(const size_t block_size)
> >
> > function for colony/hive, as this would allow the user to ascertain
> the
> > amount of memory used by a memory block's metadata in colony
> (including
> > skipfield), given the number of elements stored in that memory block.
> > This is less important for colony which is a fixed implementation,
> more
> > important for std::hive which could potentially have many alternative
> > implementations and these might not be visible to the user in text
> form.
> >
> > The idea was that if someone knows how much memory is used by each
> > block
> > outside of the actual memory used to store the elements, that might
> aid
> > in terms of knowing how much cache space is used by the metadata and
> > people might be able to make better decisions about the min/max
> > capacities of memory blocks (if they are specifying these manually)
> on
> > that basis.
> >
> > The function would throw an exception if the block_size specified was
> > outside the minimum/maximum block capacity ranges.
> >
> > My main question to you is whether this function is worth including
> > - as
> > it adds yet another function to the codebase.
> > Thanks,
> > M@
> >
> >
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