LaTeX tables in definition lists (and other lists?)

[bpj]

'Today I found that tables inside definition list values get badly vertically misaligned, appearing above instead of below the term.

So with Markdown like this

Alpha
:   Some text here

Beta

:   | 1 | 2 | 3
    |:---|:---|:---
    | delta | epsilon | zeta
    | eta | theta | iota
    | kappa | lambda | mu
    | nu | xi | omicron
    | pi | rho | sigma
    
    : Delta to sigma
    
Gamma

:   | 1 | 2 | 3
    |:---|:---|:---
    | tau | upsilon | phi
    | chi | psi | omega

    : Tau to omega.

I get results like this:

However there is an easy solution: wrapping each description containig a table in a top-aligned minipage.

Gamma
:   `\begin{minipage}[t]{0.4\textwidth}\vspace{0pt}`{=latex}

    | 1 | 2 | 3
    |:---|:---|:---
    | tau | upsilon | phi
    | chi | psi | omega
    
    : Tau to omega.

    `\end{minipage}`{=latex}

Which gives

The \vspace{0pt} is important: it ensures uniform vertical alignment within each minipage.

You can also put

\setlength\LTleft{0pt}
\setlength\LTright\fill

in your LaTeX preamble, but you still want the top-aligned minipage!

It is helpful to adjust the width of the minipage so that the tables don’t appear so far to the right, but unfortunately there (of course) is no single value which fit all: I used 0.4\textwidth for both tables, which as you can see gives better results for Beta than for Gamma. In fact I think I like it better this way than having this minipage wrapping builtin in the latex writer precisely because I can tweak the width (and maybe alignment?) of each minipage.

I don’t really like to litter my markdown with raw LaTeX markup so I wrote a filter which inserts the LaTeX based on a div with attributes which hopefully will be useful with other formats as well.

-- Define these outside the function
local begin_mp_fmt =
  '\\begin{minipage}[%s]{%.02f\\textwidth}\\vspace{0pt}'
local end_mp = pandoc.RawBlock('latex', '\\end{minipage}')

Div = function(elem)
  -- Do nothing unless it has the .minipage class
  if not (elem.classes:includes('minipage')) then
    return nil
  end
  -- Get the attributes or their defaults
  local align = elem.attributes.align or 't'
  -- Need a string here bc we validate with a pattern
  local width = elem.attributes.width or '75'
  -- Validation
  if not (align:match('^[tbc]$')) then
    error('.minipage align attr must be t/b/c')
  end
  if not (width:match('^%d+$')) then
    error('.minipage width attr must be non-negative integer (percentage of \\textwidth)')
  end
  -- From percentage to fraction
  width = width / 100
  -- Create \begin{minipage}[b]{0.75\textwidth}
  local begin_mp = begin_mp_fmt:format(align, width)
  local blocks = elem.content
  blocks:insert(1, pandoc.RawBlock('latex', begin_mp))
  blocks:insert(end_mp)
  -- Should we keep the div?
  if elem.classes:includes('keep') then
    elem.content = blocks
    return elem
  end
  -- Or discard it!
  return blocks
end

Using this filter this

Gamma
:   :::{.minipage width=40}
    | 1 | 2 | 3
    |:---|:---|:---
    | tau | upsilon | phi
    | chi | psi | omega

    : Tau to omega.
    :::

if run through pandoc -L minipage.lua -w markdown-raw_tex becomes

Gamma

:   ```{=latex}
    \begin{minipage}[t]{0.40}\vspace{0pt}
    ```
      1     2         3
      ----- --------- -------
      tau   upsilon   phi
      chi   psi       omega

      : Tau to omega.

    ```{=latex}
    \end{minipage}
    ```

The div must have a class .minipage and takes some attributes:

Attribute	Default	Description
width=INT	75	Width of the minipage in percent of the textwidth.
align=A	t	The vertical alignment of the minipage (t/b/c).
.keep	none	If this class is present the wrapping div is not discarded.

I use a percentage of the textwidth as value of the width attribute so that you don’t need to quote the attribute value in the Markdown. The filter divides that value by 100 and adjusts it to two decimals in the format string to get the fractional number TeX expects.

If this StackOverflow answer holds what it promises you can use that percentage attribute in HTML as well, should you need it.

[bpj]

I just corrected a rather serious bug in the Lua filter: I had inadvertently deleted a \\textwidth in the width argument to \\begin{minipage} on line 1

[bpj]

You can also put

\setlength\LTleft{0pt}
\setlength\LTright\fill

in your LaTeX preamble, but you still want the top-aligned minipage!