Hi Vladimir,
This seems to work well :

################################
(eval-after-load "context"
  '(setq TeX-command-list
    (append
      '(
        ("context" "PATH=/home/viserion/context/tex/texmf-linux-64/bin:$PATH context --purgeall %s"
          TeX-run-command nil t :help "Run context (MarkIV)")
        ("luametatex" "PATH=/home/viserion/data/context/tex/texmf-linux-64/bin:$PATH context --purgeall %s"
          TeX-run-command nil t :help "Run context (LMTX)")
      ) TeX-command-list
    )
  )
)
################################


Thank you so much.
Fabrice


Le mar. 9 avr. 2019 à 09:04, Vladimir Lomov <lomov.vl@yandex.ru> a écrit :
Hello,
** Fabrice Couvreur [2019-04-09 00:58:46 +0200]:

> Hi Vladimir,
> I use AUCTeX and I compile with the command C-c C-c. The configuration you
> proposed for my .emacs file last time works perfectly. So I tried to do the
> same thing with context lmtx and if I add this
>
> ("ConTeXt" "PATH = /home/viserion/data/context/tex/texmf-linux-64/bin: $
> PATH context --purgeall% s"
>      TeX-run-command nil t: help "Run context (LMTX)") TeX-command-list)
> I get the message
>
> For information about GNU Emacs and the GNU system, type C-h C-a.
> File mode specification error: (wrong-type-argument symbolp (ConTeXt PATH =
> / home / viserion / data / context / tex / texmf-linux-64 / bin: $ PATH
> context -purgeall% s TeX-run-command nil t : help Run context (LMTX)))

This message tells that something wrong with your settings (I assume the
spaces in above strings are side effect of mail system). The 'cons'
function that you use allows to add only one element to a list (see
Emacs Lisp documentation). I'm not familiar very well with Emacs Lisp
but tested a bit and think this should work:

-------------------------------- 8< ------------------------------------
(eval-after-load "context"
  '(setq TeX-command-list
    (append
      '(
        ("ConTeXt" "PATH=...:$PATH context --purgeall %s"
          TeX-run-command nil t :help "Run context (MarkIV)")
        ("LMTX"    "PATH=...:$PATH context --purgeall %s"
          TeX-run-command t   t :help "Run context (LMTX)")
      ) TeX-command-list
    )
  )
)
-------------------------------- 8< ------------------------------------

I'm not absolutely sure about 'TeX-run-command' (code of AUCTeX uses
'TeX-run-TeX' for TeX stuff). You may test and use 'TeX-run-TeX' instead
of 'TeX-run-command'. Also you may change the 'nil t' to 't
(context-mode)' if you what to edit (expanded) string and only want to
see these entries for buffers set in 'context' mode.

And please check the binary name and it's location (I didn't play with
LMTX yet).

> Fabrice

---
WBR, Vladimir Lomov

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