Re: Modify writer or extensions inside a filter

[BPJ <melroch-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>]

[-- Attachment #1: Type: text/plain, Size: 9053 bytes --]

> Den fre 16 apr. 2021 15:57Albert Krewinkel <albert+pandoc-9EawChwDxG8hFhg+JK9F0w@public.gmane.org>
skrev:
>
> You could take full control of the output by creating the desired block
yourself.
>
> E.g., instead of local cb = pandoc.CodeBlock() ff., you could write
>
> return pandoc.RawBlock('markdown',
>   string.format('``` math\n%s\n```\n', text)
> )
>
> So you'd basically be creating the Markdown yourself, which is
> relatively safe in the case of code blocks (assuming that the math
> doesn't contain ```, which would be very unusual).

There is a workaround for that, assuming that three backticks is the
*minimum* length of the fence:

``````lua
local fence_len = 3

-- loop through all substrings with consecutive backticks
for ticks in text:gmatch('%`+') do

  -- How many backticks in this substring?
  local ticks_count = ticks:len()

  -- Are there more ticks in this substring than the current fence length?
  if ticks_count > fence_len then

    -- Update the fence length to be one more than the length of this
substring
    fence_len = ticks_count + 1
  end
end

local fence = string.rep('`', fence_len)

return pandoc.RawBlock('markdown',
  string.format('%s math\n%s\n%s\n', fence, text, fence)
)
``````

> HTH,
> Albert
>
>
> 'Angel Joaniquet' via pandoc-discuss <pandoc-discuss-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org>
writes:
>
> > cross-posting of
> >
https://stackoverflow.com/questions/67109880/is-it-posible-to-enable-extensions-on-pandoc-filters#comment118648930_67109880
> >
> > The reason is that I want to have all in one file, to diminish the
> > cognitive load
> >
> >
> > El viernes, 16 de abril de 2021 a las 13:41:58 UTC+2, mb21 escribió:
> >
> >> cross-posting of
> >>
https://stackoverflow.com/questions/67109880/is-it-posible-to-enable-extensions-on-pandoc-filters
> >>
> >> Why do you prefer to set this in the filter instead of on the writer? I
> >> don't think there's a way to do that... because the filter just
outputs an
> >> AST again, and what you're trying to change is happening in the
writer...
> >>
> >> On Thursday, April 15, 2021 at 4:20:32 PM UTC+2 Angel Joaniquet wrote:
> >>
> >>> The lua split function is this
> >>>
> >>>
> >>> ```lua
> >>> function split(str,pat)
> >>>    local tbl = {}
> >>>    str:gsub(pat, function(x) tbl[#tbl+1]=x end)
> >>>    return tbl
> >>> end
> >>> ```
> >>>
> >>> El jueves, 15 de abril de 2021 a las 16:08:23 UTC+2, Angel Joaniquet
> >>> escribió:
> >>>
> >>>>
> >>>> I'm trying to make a filter to transform some features of org-mode to
> >>>> GitLab-markdown (not supported by Pandoc out of the box), in
particular,
> >>>> the math blocks.
> >>>>
> >>>> The filter should work when transforming to `markdown`, but instead
of
> >>>> giving the markdown format for the math blocks (enclosed by
`$$...$$`), it
> >>>> should write the blocks as
> >>>>
> >>>>     ```  math
> >>>>     a + b = c
> >>>>     ```
> >>>>
> >>>> The preces I have now is
> >>>>
> >>>> In org-mode, the math blocks are simply the latex code:
> >>>>
> >>>> ```
> >>>> \begin{equation}
> >>>> a + b = c
> >>>> \end{equation}
> >>>> ```
> >>>>
> >>>> this is parsed as a pandoc AST `RawBlock` with format `latex`. I then
> >>>> remove the first (`\begin{equation}`) an last line
(`\end{equation}`), and
> >>>> construct a pandoc `CodeBlock` with atrributes `{"math"}`, so the
> >>>> `CodeBlock` object displays in AST as
> >>>>
> >>>> ```
> >>>> CodeBlock ("",["math"],[]) "a + b = c\n"
> >>>> ```
> >>>>
> >>>> and then I let Pandoc create the markdown document, and the written
> >>>> result is
> >>>>
> >>>>     ``` {.math}
> >>>>     a + b = c
> >>>>     ```
> >>>>
> >>>>
> >>>>
> >>>> **The question:**
> >>>> I want the bare `math`, not `{.math}` written, without the use of CLI
> >>>> options.
> >>>>
> >>>>
> >>>> I am aware that this can be done setting the Writer extension
> >>>> `fenced_code_attributes` to false (eg. `$pandoc -w
> >>>> markdown-fenced_code_attributes ...`), but I would much prefer this
done
> >>>> inside the filter.
> >>>>
> >>>> Or is it possible to set the extensions inside the filter?
> >>>>
> >>>>
> >>>> Here is my atempted lua-filter:
> >>>>
> >>>> ``` lua
> >>>> function RawBlock(rb)
> >>>>    if rb.format == "latex" then
> >>>>       local text = rb.text
> >>>>       split_text =  split(text, "[^\n]*")
> >>>>       if split_text[1] == '\\begin{equation}'  and
> >>>> split_text[#split_text-1] == '\\end{equation}' then
> >>>>          table.remove(split_text, #split_text-1)
> >>>>          table.remove(split_text, 1)
> >>>>          text = table.concat(split_text, "\n")
> >>>>          local cb = pandoc.CodeBlock()
> >>>>          cb.attr = {"",{"math"}}
> >>>>          cb.text = text
> >>>>          return cb
> >>>>       end
> >>>>    end
> >>>> end
> >>>> ```
> >>>>
> >>>>
> >>>> Kind regards,
> >>>>
> >>>> Angel
> >>>>
> >>>>
> >>>>
> >>>>
> > --
> >
-----------------------------------------------------------------------------------------------
> >
> > La información contenida en este mensaje es de carácter privado y
> > confidencial, dirigiéndose
> > exclusivamente al destinatario mencionado en el
> > encabezamiento. Si usted ha recibido este mensaje por
> > error, le informamos
> > que no debe revelar, copiar, distribuir o usarlo en ningún sentido ya
que
> > está
> > prohibido por la legislación vigente. Rogamos lo comunique al
> > remitente y borre dicho mensaje y
> > cualquier documento adjunto que pudiera
> > contener. Los datos personales que usted facilite por correo
> > electrónico
> > podrán ser tratados por Zitro SARL con el fin de responder a su
consulta o
> > atender su
> > solicitud, así como gestionar la relación comercial, contractual
> > o precontractual con usted. La base
> > legitimadora de este tratamiento es el
> > interés legítimo de Zitro, así como el mantenimiento de la
> > relación
> > contractual o de medidas precontractuales. No se cederán datos a
terceros,
> > salvo obligación
> > legal. Sus datos serán conservados durante todo el plazo
> > de duración de la relación entre usted y Zitro y,
> > una vez terminada la
> > misma, durante el plazo que determine la legislación aplicable en cada
> > momento.
> > Usted podrá ejercitar en todo momento los derechos reconocidos en
> > la normativa de protección de
> > datos, así como contactar con Zitro a través
> > de la siguiente dirección: info-1NcKPjY1c5x0ubjbjo6WXg@public.gmane.org
> > <mailto:info-1NcKPjY1c5x0ubjbjo6WXg@public.gmane.org>.
> >
> > The information contained in this message is
> > private and confidential, speaking exclusively to the
> > recipient mentioned
> > in the heading. If you have received this message by mistake, we inform
you
> > that
> > you should not disclose, copy, distribute or use it in any way because
> > it is prohibited by current law.
> > Please notify the sender and delete the
> > message and any attachment that might contain. The personal
> > data you
> > provide by email may be processed by Zitro SARL for the purpose of
> > responding to your query
> > or attending to your request, and to manage the
> > commercial, contractual or pre-contractual
> > relationship with you. The
> > legitimizing basis of this processing is the legitimate interest of
Zitro,
> > and the
> > maintenance of the contractual relationship or pre-contractual
> > measures. No data will be passed to
> > third parties unless there is a legal
> > obligation to do so. Your data will be retained throughout the term of
> > your
> > relationship with Zitro and, once that is terminated, for the term
legally
> > required at any specific
> > time. You may exercise your rights, as recognized
> > in data protection legislation, at any time, and you
> > may contact Zitro at
> > the following email address: info-1NcKPjY1c5x0ubjbjo6WXg@public.gmane.org
> > <mailto:info-1NcKPjY1c5x0ubjbjo6WXg@public.gmane.org>.
>
>
> --
> Albert Krewinkel
> GPG: 8eed e3e2 e8c5 6f18 81fe  e836 388d c0b2 1f63 1124
>
> --
> You received this message because you are subscribed to the Google Groups
"pandoc-discuss" group.
> To unsubscribe from this group and stop receiving emails from it, send an
email to pandoc-discuss+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org
> To view this discussion on the web visit
https://groups.google.com/d/msgid/pandoc-discuss/87sg3qqqn9.fsf%40zeitkraut.de
.
>

-- 
You received this message because you are subscribed to the Google Groups "pandoc-discuss" group.
To unsubscribe from this group and stop receiving emails from it, send an email to pandoc-discuss+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org
To view this discussion on the web visit https://groups.google.com/d/msgid/pandoc-discuss/CADAJKhAcUZ-Sxj1yjbp0ky%2BTdDUq5XGMKb3Kd7NhMCcoyvmBEQ%40mail.gmail.com.

[-- Attachment #2: Type: text/html, Size: 17181 bytes --]