commit b6fbbc8167b0f6eb7427cdd94b32442019f87715
parent 5f2095c942b3b4757e78fdf14e429fa96ed9284e
Author: Martin Kloeckner <mjkloeckner@gmail.com>
Date: Fri, 11 Jul 2025 21:25:41 -0300
add `fix-math.lua`
Diffstat:
| A | fix-math.lua | | | 63 | +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ |
1 file changed, 63 insertions(+), 0 deletions(-)
diff --git a/fix-math.lua b/fix-math.lua
@@ -0,0 +1,63 @@
+-- removes all `$$` surrounding \begin{align} and \begin{align*} contexts; also
+-- modifies the space after and before equations by adding \vspace{...}
+--
+-- \begin{align} .. \end{align} adds more vertical space before and after than
+-- $$ .. $$ (or \[ \] in latex notation)
+
+local eq_before_space = "-1em"
+local eq_after_space = "0em"
+local eq_align_before_space = "-0.75em"
+local eq_align_after_space = "-0.75em"
+
+local function vspace(amount)
+ return pandoc.RawBlock('latex', '\\vspace{' .. amount .. '}')
+end
+
+function walk_blocks(blocks)
+ local new_blocks = {}
+ for _, blk in ipairs(blocks) do
+ if blk.t == 'Para' then
+ -- Paras can contain inline math elements, so check and replace those as well
+ local new_inlines = {}
+ for _, inline in ipairs(blk.content) do
+ if inline.t == 'Math' and inline.mathtype == 'DisplayMath' then
+ table.insert(new_blocks, vspace(eq_before_space))
+ if inline.text:match('^\\begin{align%*?}') then
+ -- replace inline Math with RawBlock (convert Para to RawBlock)
+ table.insert(new_blocks, vspace(eq_align_before_space))
+ table.insert(new_blocks, pandoc.RawBlock('latex', inline.text))
+ table.insert(new_blocks, vspace(eq_align_after_space))
+ else
+ table.insert(new_blocks, pandoc.RawBlock('latex', '\\[' .. inline.text .. '\\]'))
+ end
+ table.insert(new_blocks, vspace(eq_after_space))
+ else
+ table.insert(new_inlines, inline)
+ end
+ end
+ -- Only add the Para if there is still content
+ if #new_inlines > 0 then
+ table.insert(new_blocks, pandoc.Para(new_inlines))
+ end
+
+ elseif blk.t == 'CodeBlock' or blk.t == 'RawBlock' then
+ -- Just keep them as is
+ table.insert(new_blocks, blk)
+
+ elseif blk.t == 'BlockQuote' or blk.t == 'Div' then
+ -- Recurse on nested blocks
+ table.insert(new_blocks, vspace("0.5em"))
+ blk.content = walk_blocks(blk.content)
+ table.insert(new_blocks, blk)
+ table.insert(new_blocks, vspace("0.5em"))
+ else
+ table.insert(new_blocks, blk)
+ end
+ end
+ return new_blocks
+end
+
+function Pandoc(doc)
+ doc.blocks = walk_blocks(doc.blocks)
+ return doc
+end
