SumatraPDF.exe as default PDF viewer

Question

I'm using emacs (GNU Emacs 25.1.1 (x86_64-w64-mingw32) of 2016-09-17), and trying to define SumatraPDF as my default PDF-viewer for LaTeX. After some trials, nothing happens, and I have no idea why...

I wrote this in my .emacs-file (just after calling the emacs-leuven configuration ):

(eval-after-load 'latex
  '(progn
     (if (eq system-type 'windows-nt)
         (progn
           (add-to-list 'TeX-view-program-list
                        '("Sumatra PDF"
                          ("\"c:/Program Files (x86)/SumatraPDF/SumatraPDF.exe\" -reuse-instance"
                           (mode-io-correlate " -forward-search %b %n") " %o")))
           (assq-delete-all 'output-pdf TeX-view-program-selection)
           (add-to-list 'TeX-view-program-selection '(output-pdf "Sumatra PDF"))))))

And this is what I see in the buffer for the customization of the TeX-view-program-list :

'(("Sumatra PDF"
   ("\"c:/Program Files (x86)/SumatraPDF/SumatraPDF.exe\" -reuse-instance"
    (mode-io-correlate " -forward-search %b %n")
    " %o"))
  ("SumatraPDF"
   (concat "\"" "c:/Program Files (x86)/SumatraPDF/SumatraPDF.exe" "\" %o")))

Does someone have any idea what's wrong ?

Answer 1

It is hard to debug the issue you describe: It would help if you could assemble a minimal scenario how to reproduce this.

Meanwhile, I can suggest the following:

• Update your AUCTeX to lastest version (11.90.2) from ELPA. It has builtin support for SumatraPDF on Windows.
• Put the directory c:/Program Files (x86)/SumatraPDF/ into your PATH on Windows.
• Restart Emacs and check if Emacs finds SumatraPDF by evaluating this line:
  (executable-find "SumatraPDF")
• Add this single line in your init file, restart Emacs and open your .tex file:
  (setq TeX-view-program-selection '((output-pdf "SumatraPDF")))

Not related to your problem, I think emacs-leuven has a bug here:

(when (or leuven--win32-p leuven--cygwin-p)
  (when (boundp 'TeX-view-program-list)
    (add-to-list 'TeX-view-program-list
                 `("SumatraPDF"
                   (concat "\"" ,leuven--sumatrapdf-command "\" %o")))))

Observe where the , is. This way, it adds a concat to TeX-view-program-list which will not work (see your question). The correct way would be:

(when (or leuven--win32-p leuven--cygwin-p)
  (when (boundp 'TeX-view-program-list)
    (add-to-list 'TeX-view-program-list
         `("SumatraPDF"
           ,(list (concat "\"" leuven--sumatrapdf-command "\" %o"))))))

And for your code, I suggest you don't rely on assq-delete-all deleting items from a list. To be on the safe side, do:

(setq TeX-view-program-selection
      (assq-delete-all 'output-pdf TeX-view-program-selection))