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

Hello, Theo.

On Wed, Nov 17, 2021 at 23:32:41 +0100, Theodor Thornhill wrote:
> Hi Alan!

> >> Thanks again for working on this!  There is already one user reporting
> >> that huge slowdowns aren't occurring anymore given that pr.  There are
> >> probably still stuff to iron out, ....

> > I think that's highly likely.  That's why I've left it a little while
> > before merging it into Emacs itself.


> Ok, so now I have my first bug report with the new implementation on my
> hands [1]. I must say I don't fully understand what is going on here.
> To me it seems like CC mode is now treating _all_ strings as multiline
> strings, even the ones not using the `@` prefix. Is that supposed to be
> expressed somehow?  I think what the problem boils down to is this:

> ```
> string s1 = "He said, \"This is the last \u0063hance\x0021\"";
> string s2 = @"He said, ""This is the last \u0063hance\x0021""";

> Console.WriteLine(s1);
> Console.WriteLine(s2);
> // The example displays the following output:
> //     He said, "This is the last chance!"
> //     He said, "This is the last \u0063hance\x0021"
> ```

> I am not sure if this is because of the regexes or the general
> implementation, so maybe you can point me in the correct direction? A
> good screenshot is provided in the link below.  I don't know if you use
> GitHub, so I'll attach that aswell.  Sorry to bother you with this!

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.

> > Well, congratulations!  I can understand the bit about it "taking some
> > time".  ;-)


> Thanks :)


> > Thanks, more or less yes.  I hope everything's OK at your end, too.


> Apart from my kids having their 45th or so cold this fall, then yes :)

Oh, that's not nice.  Not a big worry, but unpleasant all the same.

> Theo

> [1]: https://github.com/emacs-csharp/csharp-mode/issues/252

-- 
Alan Mackenzie (Nuremberg, Germany).