Re: Adding support for xref jumping to headers/interfaces

[Dmitry Gutov]

On 05/03/2023 14:06, Dmitry Gutov wrote:
> > For C-like languages, we'd need to run "etags --declarations" on *.h
> > files for that, I think.  And the resulting TAGS table will have stuff
> > other than just declarations, so we'd need some way of distinguishing
> > between them and the rest.
>
> The etags xref backend usually works with pre-generated tags files. So a 
> way to distinguish between them and the rest would be best.

To expand on that thought: Universal Ctags has a bunch of extensions for 
the output -- in particular the "kind" field.

After 'sudo apt install universal-ctags', I can see this:

  $ ctags --list-kinds=c
  d  macro definitions
  e  enumerators (values inside an enumeration)
  f  function definitions
  g  enumeration names
  h  included header files
  l  local variables [off]
  m  struct, and union members
  p  function prototypes [off]
  s  structure names
  t  typedefs
  u  union names
  v  variable definitions
  x  external and forward variable declarations [off]
  z  function parameters inside function or prototype definitions [off]
  L  goto labels [off]
  D  parameters inside macro definitions [off]

That seems to mean that it can distinguish "function prototypes" and 
"forward variable declarations", although their scanning seems to be 
disabled by default (can be toggled via --kinds-c=+p+x).

So I suppose the question here is how hard it would be to add to 
existing etags parsers something like that, and whether we can extend 
the TAGS format in a backward compatible way with this info.