Hello,
I have this test case; export it by doing C-c C-e C-s m M (assuming ox-md is required.. I think it is required by default).
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* Escaping hashes and exclamations correctly in body
:PROPERTIES:
:EXPORT_FILE_NAME: escaping-hashes-and-exclamations-in-body
:END:
I intend to show these # characters verbatim; they should not render
as Markdown headings. They also shouldn't show up with a leading =\=
in the final rendered output.
# This is an Org comment
#This is not an Org comment. It has a hash char at beginning of a
paragraph which must be escaped just once i.e. show up as =\#= in
Markdown.
blah # This isn't an Org comment either
This * will be escaped just once i.e. show up as =\*= in Markdown.
This _ will be escaped just once i.e. show up as =\_= in Markdown.
This \ will be escaped just once i.e. show up as =\\= in Markdown.
Hash char at beginning of a continued line
#like this must be escaped just once i.e. show up as =\#= in Markdown.
![this exclamation must be escaped just once i.e. show up as =\!= in
Markdown]
This ! does not need to be escaped as there is no ambiguity.
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Here's the relevant excerpt of the export that is erroneous:
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Hash char at beginning of a continued line
\\#like this must be escaped just once i.e. show up as `\#` in Markdown.
\\![this exclamation must be escaped just once i.e. show up as `\!` in
Markdown]
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Note that the # and ![ are double-escaped. So any markdown->HTML renderer will print that "\" as it is.
Digging through ox-md.el, I found that the order of replace-regexp-in-string was incorrect in org-md-plain-text.
Here's the diff:
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diff --git a/lisp/ox-md.el b/lisp/ox-md.el
index 12188387355..927a73b780c 100644
--- a/lisp/ox-md.el
+++ b/lisp/ox-md.el
@@ -500,14 +500,15 @@ TEXT is the string to transcode. INFO is a plist holding
contextual information."
(when (plist-get info :with-smart-quotes)
(setq text (org-export-activate-smart-quotes text :html info)))
+ ;; The below series of replacements in `text' is order sensitive.
+ ;; Protect `, *, _, and \
+ (setq text (replace-regexp-in-string "[`*_\\]" "\\\\\\&" text))
;; Protect ambiguous #. This will protect # at the beginning of
;; a line, but not at the beginning of a paragraph. See
;; `org-md-paragraph'.
(setq text (replace-regexp-in-string "\n#" "\n\\\\#" text))
;; Protect ambiguous !
(setq text (replace-regexp-in-string "\\(!\\)\\[" "\\\\!" text nil nil 1))
- ;; Protect `, *, _ and \
- (setq text (replace-regexp-in-string "[`*_\\]" "\\\\\\&" text))
;; Handle special strings, if required.
(when (plist-get info :with-special-strings)
(setq text (org-html-convert-special-strings text)))
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After applying this patch, the same portion exported doesn't have double-escaping before # and ![.