Lua 5.4 is used by default after this is merged. Packagers may still include Lua 5.3
instead by building pandoc with `--constraint='hslua <2.2'`.
Differences between 5.3 and 5.4 should not generally affect pandoc Lua filters.
See list of incompatible changes here <https://www.lua.org/manual/5.4/manual.html#8.1>
- Allow any type of callable object as argument to List
functions `filter`, `map`, and `find_if`. These previously
required the argument to be of type `function`, which was too
restrictive.
- Inline: the type of Image captions is now `Inlines` instead
of `List`.
The objects now also follow the principle that element attributes are
accessible through the `.attr` field. Rows in `TableHead` and
`TableFoot` are available via the `.rows` field. Row objects have a
`.cells` field, containing the list of table cells.
Closes: #7718
The traversal order of filters can now be selected by setting the key
`traverse` of the filter to either `'topdown'` or `'typewise'`; the
default remains `'typewise'`.
Topdown traversals can be cut short by returning `false` as a second
value from the filter function. No child-element of the returned element
is processed in that case.
- `walk` methods are added to `Block` and `Inline` values; the methods
are similar to `pandoc.utils.walk_block` and
`pandoc.utils.walk_inline`, but apply to filter also to the element
itself, and therefore return a list of element instead of a single
element.
- Functions of name `Doc` are no longer accepted as alternatives for
`Pandoc` filter functions. This functionality was undocumented.
The marshaling functions for pandoc's AST are extracted into a separate
package. The package comes with a number of changes:
- Pandoc's List module was rewritten in C, thereby improving error
messages.
- Lists of `Block` and `Inline` elements are marshaled using the new
list types `Blocks` and `Inlines`, respectively. These types
currently behave identical to the generic List type, but give better
error messages. This also opens up the possibility of adding
element-specific methods to these lists in the future.
- Elements of type `MetaValue` are no longer pushed as values which
have `.t` and `.tag` properties. This was already true for
`MetaString` and `MetaBool` values, which are still marshaled as Lua
strings and booleans, respectively. Affected values:
+ `MetaBlocks` values are marshaled as a `Blocks` list;
+ `MetaInlines` values are marshaled as a `Inlines` list;
+ `MetaList` values are marshaled as a generic pandoc `List`s.
+ `MetaMap` values are marshaled as plain tables and no longer
given any metatable.
- The test suite for marshaled objects and their constructors has
been extended and improved.
- A bug in Citation objects, where setting a citation's suffix
modified it's prefix, has been fixed.
Compiles the 'lpeg' library (Parsing Expression Grammars For Lua) into
the program.
Package maintainers may choose to rely on package dependencies to make
lpeg available, in which case they can compile the with the constraint
`lpeg +rely-on-shared-lpeg-library`.
This fixes issues with
- misleading error messages when a required function parameter is
omitted;
- absent properties still being listed in the output of `pairs`; and
- alias accessing leading to errors instead of returning `nil`, e.g.
with `(pandoc.Str '').identifier`.
Fixes: #7661
See also: #7657
