Re: [v3] Revised locale caches

["B. Kosnik" <bkoz at nabi dot net>]

>1) If someone specializes numpunct<sometype>, there probably won't be
>   a cache.  With the solution I had posted, we will still cache the
>   values.  The only way for that to work is to have it outside the
>   facet itself - or perhaps in locale::facet, where everyone is
>   forced to pick it up.

Let me think some more about this. I'm looking at examples, but I think
it is possible.

>   If you think that this issue isn't important enough to keep the
>   caches external to the facets, then I won't argue the point
>   further.

I think it can be worked around by re-arranging the templates. 

>1) There should probably be an accessor to the underlying cache data,
>   rather than relying on numpunct == numpunct_cache*

Agreed.

>2) I'd rather see the __use_cache function in the tcc file as a
>   template.  Except then we run afoul of #1 :-(
>
>   Moving the __use_cache function specializations here buys a 2-3%
>   speedup on the int output test.

Agreed. This part is pretty flimsy.

>3) I don't think we need the allocated flag.  The only time the data
>   isn't allocated is for the posix locale, and the destructor will
>   never run.

Vestigial data... you are right. I'll fix this.

>4) It's not safe to require the existence of ctype in setting up the
>   numpunct cache.  Some uses will not require it, and shouldn't blow
>   up as a result.  My posted solution suffers from a similar issue.

I think this is ok as long as the cache is used when both facets need to
be present. I'll look at this tomorrow.

>6) This can't be backported to 3.3 since it changes the ABI.  So, can
>   we keep the version I posted alive for that?  I'm pretty confident
>   I can make that work in 3.3 within the ABI.  Including a cache per
>   facet.

Sounds like a plan.

>It's too late tonight, but I'll do the minor changes above tomorrow
>night.

Alright then. I'll check this in, and we can both work from it.

> > Let me know what you think. I'd like to go through and do num_get
> > (painless now), as well as the other data facets (__timepunct,
> > __moneypuncts) in a similar style.
>
>Can we get this in first and then do the other facets? :-)

Agreed.

-benjamin