bug#20650: 25.0.50; xref seems not to pick C++ destructors

[Eli Zaretskii]

> From: Dmitry Gutov <dgutov@yandex.ru>
> Date: Tue, 26 May 2015 02:21:41 +0300
> 
> On 05/25/2015 06:27 PM, Eli Zaretskii wrote:
> 
> > the tags table is OK, it's xref that
> > didn't understand that when point is on "~A", you want ~A, not A.
> 
> You're welcome to suggest a better implementation for 
> xref-default-identifier-at-point (keep in mind that it should be 
> language-agnostic), but while it uses (thing-at-point 'symbol), maybe 
> c++-mode should propertize ~ in those positions to have syntax class 
> "symbol".

My point was precisely that xref is not smart enough when it picks the
symbol.  If we need some languages to help it, we should make sure all
supported languages provide that.  It's no use asking etags for better
precision when xref cannot pick up the right symbol.

> Normally it's performed with a syntax-propertize-function, but c++-mode 
> doesn't have it.

Well, perhaps it should.