[O] Feature request: export vertical/horizontal table lines in math mode [9.0 (release_9.0-16-g8826f2 @ /Users/stefanos/org-mode/lisp/)]

[Stefanos Carlström]

In a previous version of Org [Emacs 24.4.90.2 (Org mode 8.2.10)
according to an old PDF I have], I could export an Org table as a matrix
in math mode and divide the matrix into sub-blocks with the alignment
string and \hline's. The former is no longer possible in the HEAD
version of Org. This works fine, in normal mode, both
vertical/horizontal dividers exported:

    #+ATTR_LATEX: :align c|c
    | a | b |
    |---+---|
    | c | d |

exports to

    \begin{center}
    \begin{tabular}{c|c}
    a & b\\
    \hline
    c & d\\
    \end{tabular}
    \end{center}

whereas

    #+ATTR_LATEX: :mode math :environment array :align c|c :math-prefix 
A=\left[ :math-suffix \right],
    | a         | b |
    |-----------+---|
    | \hline{}c | d |

exports to

    \[
    A=\left[\begin{array}{cc}
     a & b \\
     \hline{}c & d \\
    \end{array}\right],
    \]

First off, I would like the vertical dividing line back. If I could also
(maybe via an option) get the horizontal line without manually adding
the \hline, it would be fantastic!

Cheers,
Stefanos

Emacs  : GNU Emacs 25.1.1 (x86_64-apple-darwin13.4.0, NS appkit-1265.21 Version 
10.9.5 (Build 13F1911))
 of 2016-09-21
Package: Org mode version 9.0 (release_9.0-16-g8826f2 @ 
/Users/stefanos/org-mode/lisp/)

current state:
==============
(setq
 org-hide-leading-stars t
 org-pandoc-epub-rights "Copyright 2016 Stefanos Carlström <>"
 org-tab-first-hook '(org-babel-hide-result-toggle-maybe
                      org-babel-header-arg-expand)
 outline-minor-mode-hook '(outshine-hook-function)
 org-latex-classes '(("beamer" "\\documentclass[presentation]{beamer}"
                      ("\\section{%s}" . "\\section*{%s}")
                      ("\\subsection{%s}" . "\\subsection*{%s}")
                      ("\\subsubsection{%s}" . "\\subsubsection*{%s}"))
                     ("article" "\\documentclass[11pt]{article}"
                      ("\\section{%s}" . "\\section*{%s}")
                      ("\\subsection{%s}" . "\\subsection*{%s}")
                      ("\\subsubsection{%s}" . "\\subsubsection*{%s}")
                      ("\\paragraph{%s}" . "\\paragraph*{%s}")
                      ("\\subparagraph{%s}" . "\\subparagraph*{%s}"))
                     ("report" "\\documentclass[11pt]{report}"
                      ("\\part{%s}" . "\\part*{%s}")
                      ("\\chapter{%s}" . "\\chapter*{%s}")
                      ("\\section{%s}" . "\\section*{%s}")
                      ("\\subsection{%s}" . "\\subsection*{%s}")
                      ("\\subsubsection{%s}" . "\\subsubsection*{%s}"))
                     ("book" "\\documentclass[11pt]{book}"
                      ("\\part{%s}" . "\\part*{%s}")
                      ("\\chapter{%s}" . "\\chapter*{%s}")
                      ("\\section{%s}" . "\\section*{%s}")
                      ("\\subsection{%s}" . "\\subsection*{%s}")
                      ("\\subsubsection{%s}" . "\\subsubsection*{%s}"))
                     ("landau-book" "\\documentclass[11pt]{book}"
                      ("\\chapter{%s}" . "\\chapter*{%s}")
                      ("\\section{%s}" . "\\section*{%s}")
                      ("\\subsection{%s}" . "\\subsection*{%s}")
                      ("\\subsubsection{%s}" . "\\subsubsection*{%s}"))
                     )
 org-speed-command-hook '(org-speed-command-default-hook
                          org-babel-speed-command-hook)
 org-occur-hook '(org-first-headline-recenter)
 org-metaup-hook '(org-babel-load-in-session-maybe)
 org-html-format-drawer-function #[514 "\207" [] 3 "\n\n(fn NAME CONTENTS)"]
 org-format-latex-options '(:foreground default :background default :scale 2
                            :html-foreground "Black" :html-background
                            "Transparent" :html-scale 1.0 :matchers
                            ("begin" "$1" "$" "$$" "\\(" "\\["))
 org-latex-format-inlinetask-function 
'org-latex-format-inlinetask-default-function
 org-confirm-shell-link-function 'yes-or-no-p
 org-ascii-format-inlinetask-function 'org-ascii-format-inlinetask-default
 org-latex-pdf-process '("latexmk -pdflatex='pdflatex -shell-escape' -pdf %f")
 org-preview-latex-default-process 'imagemagick
 org-babel-clojure-backend 'cider
 org-latex-format-headline-function 'org-latex-format-headline-default-function
 org-default-notes-file "/Users/stefanos/org/notes.org"
 org-after-todo-state-change-hook '(org-clock-out-if-current)
 org-latex-format-drawer-function #[514 "\207" [] 3 "\n\n(fn _ CONTENTS)"]
 org-odt-format-headline-function 'org-odt-format-headline-default-function
 org-from-is-user-regexp "\\<Stefanos Carlström\\>"
 org-src-mode-hook '(org-src-babel-configure-edit-buffer
                     org-src-mode-configure-edit-buffer)
 org-agenda-before-write-hook '(org-agenda-add-entry-text)
 org-babel-pre-tangle-hook '(save-buffer)
 org-trigger-hook '(org-depend-trigger-todo)
 org-archive-hook '(org-attach-archive-delete-maybe)
 org-ascii-format-drawer-function #[771 "
\207" [] 4 "\n\n(fn NAME CONTENTS 
WIDTH)"]
 org-odt-format-inlinetask-function 'org-odt-format-inlinetask-default-function
 org-directory "/Users/stefanos/org"
 org-cycle-hook '(org-cycle-hide-archived-subtrees org-cycle-hide-drawers
                  org-cycle-show-empty-lines
                  org-optimize-window-after-visibility-change)
 org-export-before-processing-hook '(my-auto-tex-cmd)
 org-babel-python-command "python3"
 org-download-annotate-function 'org-download-annotate-default
 org-babel-tangle-lang-exts '(("clojure" . "clj") ("ruby" . "rb") ("D" . "d")
                              ("C++" . "cpp") ("julia" . "jl") ("python" . "py")
                              ("emacs-lisp" . "el") ("elisp" . "el"))
 org-confirm-elisp-link-function 'yes-or-no-p
 org-metadown-hook '(org-babel-pop-to-session-maybe)
 org-odt-format-drawer-function #[514 "\207" [] 3 "\n\n(fn NAME CONTENTS)"]
 org-babel-after-execute-hook '(org-display-inline-images)
 org-latex-listings 'minted
 org-blocker-hook '(org-depend-block-todo)
 org-html-format-headline-function 'org-html-format-headline-default-function
 org-babel-load-languages '((python . t) (emacs-lisp . t) (calc . t) (julia . t)
                            (C . t) (sh . t) (ruby . t) (clojure . t) (octave . 
t))
 org-html-format-inlinetask-function 
'org-html-format-inlinetask-default-function
 org-agenda-files '("~/org/todo.org" "~/org/notes.org")
 org-clock-out-hook '(org-clock-remove-empty-clock-drawer)
 org-confirm-babel-evaluate nil
 )