From 6174b5bea5e8c4c35c191bd62f1f42e4d7fce69e Mon Sep 17 00:00:00 2001
From: John MacFarlane <jgm@berkeley.edu>
Date: Sat, 11 Nov 2017 11:01:38 -0500
Subject: Add lua filter functions to walk inline and block elements.
Refactored some code from Text.Pandoc.Lua.PandocModule
into new internal module Text.Pandoc.Lua.Filter.
Add `walk_inline` and `walk_block` in pandoc lua module.
---
doc/lua-filters.md | 49 ++++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 48 insertions(+), 1 deletion(-)
(limited to 'doc')
diff --git a/doc/lua-filters.md b/doc/lua-filters.md
index 8c8268c20..1e0b988ba 100644
--- a/doc/lua-filters.md
+++ b/doc/lua-filters.md
@@ -165,6 +165,8 @@ those elements accessible through the filter function parameter.
Some pandoc functions have been made available in lua:
+- `walk_block` and `walk_inline` allow filters to be applied
+ inside specific block or inline elements.
- `read` allows filters to parse strings into pandoc documents
- `pipe` runs an external command with input from and output to
strings
@@ -333,6 +335,20 @@ will output:
</dl>
```
+## Uppercasing text inside all headers
+
+This filter uses `walk_block` to transform inline elements
+inside headers, converting all their text into uppercase.
+
+``` lua
+function Header(el)
+ return pandoc.walk_block(el, {
+ Str = function(el)
+ return pandoc.Str(el.text:upper())
+ end })
+end
+```
+
## Converting ABC code to music notation
This filter replaces code blocks with class `abc` with
@@ -1070,6 +1086,38 @@ Lua functions for pandoc scripts.
## Helper Functions
+[`walk_block (element, filter)`]{#walk_block}
+
+: Apply a filter inside a block element, walking its
+ contents.
+
+ Parameters:
+
+ `element`:
+ : the block element
+
+ `filter`:
+ : a lua filter (table of functions) to be applied
+ within the block element
+
+ Returns: the transformed block element
+
+[`walk_inline (element, filter)`]{#walk_inline}
+
+: Apply a filter inside an inline element, walking its
+ contents.
+
+ Parameters:
+
+ `element`:
+ : the inline element
+
+ `filter`:
+ : a lua filter (table of functions) to be applied
+ within the inline element
+
+ Returns: the transformed inline element
+
[`read (markup[, format])`]{#read}
: Parse the given string into a Pandoc document.
@@ -1142,7 +1190,6 @@ Lua functions for pandoc scripts.
local output = pandoc.pipe("sed", {"-e","s/a/b/"}, "abc")
-
# Submodule mediabag
The submodule `mediabag` allows accessing pandoc's media
--
cgit v1.2.3