bug#15212: 24.3.50; c++-mode doesn't support raw string literals

[Alan Mackenzie]

Hello, Michael.

On Tue, Jun 07, 2016 at 06:06:17PM -0400, Michael Welsh Duggan wrote:
> Since you are working on string handling I thought I would verify
> whether you handle the following:

> Every string literal, including raw string literals, may be proceeded by
> an encoding-prefix (no space separating).  The valid encoding-prefixes
> are:

> u8 u U L

> Examples from the standard:

> "..."
> R"(...)"
> u8"..."
> u8R"**(...)**"
> u"..."
> uR"*~(..)*~"
> U"..."
> UR"zzz(...)zzz"
> L"..."
> LR"(...)"

> The meanings of these prefixes are:

> u8: UTF-8 string literal
> u:  char16_t literal
> U:  char32_t literal
> L:  wchar_t literal

Thanks!  I hadn't forgotten about them, I was more postponing them until
the more difficult stuff was done.  To be honest, I'm not sure how much,
if any, special handling they'll need - as far as CC Mode is concerned,
they have no syntactic significance, I think.  The only thing I can
think of at the moment (and it is after midnight here) is that one of
the prefixes prefixing an unterminated raw string might also get
font-lock-warning face, just like the raw string delimiter.  Maybe.

By the way, I haven't forgotten about the state-cache bug, though I've
not made much progress on it, yet.

> -- 
> Michael Welsh Duggan
> (md5i@md5i.com)

-- 
Alan Mackenzie (Nuremberg, Germany).