Help with etags

Help with etags

[N. Raghavendra]

I am trying to build a tags table for some files which look like this

------------------------File: Homotopies.v ---------------------------
Require Export Paths.

Definition
  homotopies
  {X Y : U} (f g : X -> Y)
  : U
  := prod (x : X) , (paths (f x) (g x)).

Notation
  "f ~ g"
  := (homotopies f g).

Definition
  function_induced_function_homotopic_identity
  {X : U} (f : X -> X) (h : f ~ (Functions.identity X)) (x y : X)
  (p : paths x y)
  : paths ((induced_function f p) @ (h y)) ((h x) @ p).
----------------------------------------------------------------------

I want the tags table to show the identifier in every line following a
line containing `Definition', e.g., `homotopies' and
`function_induced_function_homotopic_identity'.

I tried the command

etags --language=none --regex="/^[[:space:]]*Definition[[:space:]\n]+[[:space:]]*\([[:alnum:]_]+\)[[:space:]]*\n/\1/" Homotopies.v

but am getting an empty tags table.  What is the right way to generate
tags for such files?

Thanks,
Raghu.

--
N. Raghavendra <raghu@hri.res.in>, http://www.retrotexts.net/
Harish-Chandra Research Institute, http://www.hri.res.in/

Re: Help with etags

[Eli Zaretskii]

> From: "N. Raghavendra" <nyraghu27132@gmail.com>
> Date: Tue, 05 Dec 2017 18:23:47 +0530
> 
> I tried the command
> 
> etags --language=none --regex="/^[[:space:]]*Definition[[:space:]\n]+[[:space:]]*\([[:alnum:]_]+\)[[:space:]]*\n/\1/" Homotopies.v
> 
> but am getting an empty tags table.

This is because (a) you should drop the leading "^" in the regexp
(the regexp is always used anchored, as described in the manual);
and (b) you should use the 'm' modifier, because your regexp is
multi-line (this is also in the manual).

This works for me:

  etags --language=none --regex="/[[:space:]]*Definition[[:space:]\n]+[[:space:]]*\([[:alnum:]_]+\)[[:space:]]*\n/\1/m" Homotopies.v

Re: Help with etags

[N. Raghavendra]

At 2017-12-08T12:28:33+02:00, Eli Zaretskii wrote:

> This works for me:
>
>   etags --language=none
> --regex="/[[:space:]]*Definition[[:space:]\n]+[[:space:]]*\([[:alnum:]_]+\)[[:space:]]*\n/\1/m"
> Homotopies.v

Thank you.  I tried that regex on my files.  It produces a tags table,
but when I use the table, and do M-. at an identifier, it takes me to
the wrong places in the files.

Meanwhile, I found the Perl program `coqtags', distributed with Emacs
Proof General, for tagging Coq files, such as the ones I am trying to
tag, and it works well.

Kind regards,
Raghu.

-- 
N. Raghavendra <raghu@hri.res.in>, http://www.retrotexts.net/
Harish-Chandra Research Institute, http://www.hri.res.in/