Re: CC Mode multi-line strings [Was: Adding Vala support]

Hello, Theo.

On Thu, Nov 18, 2021 at 20:31:59 +0100, Theodor Thornhill wrote:

> Hi Alan!

> > No problem!  My guess is that inside the @" string, there are no escape
> > characters.  So "\u0063" stands for the six characters \ u 0 0 6 3
> > rather than the single unicode c.  If that's the case, then this isn't a
> > problem with C# Mode or CC Mode.

> Hmm, that might be true, however I think there still is a problem
> somewhere.

Yes.  Apologies for not looking at the attached picture.  (I read my
email in mutt on a tty, usually.)

> For example:

> ```
> var x = "Hello, \"World\"";
> ```
> In this case, `Hello, \"` is fontified as a string, then `World \"` has
> no fontification, then, the last `"` has a warning face, then at last,
> the `;` is fontified as a string.

I downloaded the current csharp-mode from github, and I think the
settings for the c-ml-string-... are not quite right.

For example, in c-ml-string-opener-re, there is no "@" in it.  I don't
think this particular regexp need be complicated.  Why won't a simple
"\\(@\\(\"\\)\\)" do?  (Sorry, I'm not practiced at the rx form of
regexps.)

In c-ml-string-back-closer-re, it looks like : and ? may have got
swapped in "\\(:?" - shouldn't that be "\\(?:"?

Indeed, looking back at some earlier versions of my files, I think I can
see the origin of some of these discrepanceies.  ;-)

> This will cause the next expressions to be fontified as strings as
> well, possibly rendering the whole file as a string.  It seems to make
> no difference if the string is preceeded with a `@`.  It seems like
> escaping quotes is not working properly somehow.

See above.

> What am I missing :)?

These regexps are quite a tricky part of CC Mode.  Sorry about that.

> All the best,
> Theo!

-- 
Alan Mackenzie (Nuremberg, Germany).