RE: FW: Font-lock misfontifies foo::bar in C++

[Marshall, Simon]

> > Martin, can you shed any light upon why "foo" in "foo::bar" is given 
> > c-reference-face-name?
> 
> Sure. "foo" doesn't get the type face since it isn't used as 
> a type - it's used as an identifier qualifier. Note that 
> "foo" in a "foo::bar"
> expression can be a namespace name too, which isn't a type at all.

Alan, I already explained that it was either a type name or a namespace
name.
My point was that it definitely is *not* a reference (a constant or label).

> Example 3:
> 
>     foo::bar
> 
> "foo" doesn't specify the type of anything here either. Its 
> use is to tell in which scope "bar" is declared. Hence it 
> gets a face that is different from the type face. I call this 
> use "identifier qualifier".
> 
> To make this more obvious/precise, you could perhaps 
> introduce another face name variable, say 
> c-qualifier-face-name, and make a suitable mapping of it onto 
> one of the existing font-lock faces. I don't think it should 
> be mapped to the type face though, because it would be used 
> for namespace names too. In lack of better alternatives I 
> chose to map it as I did.

I think c-qualifier-face-name would be a good idea, but I think it odd to
pick a face for its value that is definitely wrong.  References are used for
constants and labels.  Why not pick a face that is usually right, eg, the
type face?

Perhaps a better solution would be to add a c++-font-lock-extra-qualifiers,
akin to c++-font-lock-extra-types, that is a list of qualifier names.  I
would suggest that, by default, these could be fontified in
font-lock-type-face, but perhaps you might like to add a
font-lock-qualifier-face to allow users (or modes) to specify what they
want.  For C++, this variable could default to '("std") or somesuch.  

So, by default, "foo::bar" would not cause "foo" to be fontified in any
face.  If the user wanted it to be fontified, they would modify
c++-font-lock-extra-types if it were a type or
c++-font-lock-extra-qualifiers if it were a namespace.

WDYT?  I'm not on either mailing list, so please CC: me on any reply.

Thanks, Simon.