On Sat, 4 Jan 2020 at 15:12, Thiago Macieira via SG16 <sg16_at_[hidden]>
wrote:

> On Tuesday, 31 December 2019 20:49:00 -03 Tom Honermann via SG16 wrote:
> > The benefit is that including all of them avoids the problem of
> > implementors offering extensions with inconsistent or conflicting
> > names. It also doesn't put us in the position of deciding which
> > encodings are "important". IANA provides a good specification to
> > follow. I don't think we should be subsetting, at least not without
> > some clear criteria for determining which encodings make the cut. For
> > example, I suspect Shift-JIS gets more use than UTF-32, but the former
> > is not included in the proposal and the latter is.
>
> I say we should bite that bullet and make the list of what we think should
> be
> available as constexpr-time constants: 7-bit US-ASCII, Latin1, UTF-8,
> UTF-16,
> UTF-32. Plus something to indicate "System" (locale encoding). No more.
>
> If someone needs a full listing, they can take the XML file from IANA and
> generate their list converting from MIB to all names and aliases. The C++
> standard doesn't need to do that for them.
>
> Besides, what are the IDs to be used for? To access an encoder and a
> decoder?
> Aside from those 6 above, everything else, including unregistered names,
> aliases and extensions, is optional to all implementations and must be
> checked
> for at runtime. Relying on them existing is not portable.
>

Comparison.... basically the only use (2 text encoding with the same mib
are identical, although the primary iana name might do), and you can
compare a MiB to a text_encoding directly.
I still think it's useful to have a method that gives you the mib when it
is known so you can interface with a few libraries that use it.
But beyond that I don't think we should focus on MiB.

Otherwise I agree, an implementation needs to only provide the encoding it
cares about.
(important for embedded platforms where the encoding never changes)


>
> --
> Thiago Macieira - thiago (AT) macieira.info - thiago (AT) kde.org
> Software Architect - Intel System Software Products
>
>
>
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