This change makes it possible to define a catch-all function using lua's
metatable lookup functionality.
function catch_all(el)
…
end
return {
setmetatable({}, {__index = function(_) return catch_all end})
}
A further effect of this change is that the map with filter functions
now only contains functions corresponding to AST element constructors.
No more SingleQuoted, DoubleQuoted, InlineMath, DisplayMath.
This makes everything uniform and predictable, though it does
open up a difference btw lua filters and custom writers.
The implicitly defined global filter (i.e. all element filtering
functions defined in the global lua environment) is used if no filter is
returned from a lua script. This allows to just write top-level
functions in order to define a lua filter. E.g
function Emph(elem) return pandoc.Strong(elem.content) end
A single `read` function parsing pandoc-supported formats is added to
the module. This is simpler and more convenient than the previous method
of exposing all reader functions individually.
Filtering functions take element components as arguments instead of the
whole block elements. This resembles the way elements are handled in
custom writers.
Instead of taking the whole inline element, forcing users to destructure it
themselves, the components of the elements are passed to the filtering
functions.
Plain text readers are exposed to lua scripts via the `pandoc.reader`
submodule, which is further subdivided by format. Converting e.g. a
markdown string into a pandoc document is possible from within lua:
doc = pandoc.reader.markdown.read_doc("Hello, World!")
A `read_block` convenience function is provided for all formats,
although it will still parse the whole string but return only the first
block as the result.
Custom reader options are not supported yet, default options are used
for all parsing operations.
* Add `--lua-filter` option. This works like `--filter` but takes pathnames of special lua filters and uses the lua interpreter baked into pandoc, so that no external interpreter is needed. Note that lua filters are all applied after regular filters, regardless of their position on the command line.
* Add Text.Pandoc.Lua, exporting `runLuaFilter`. Add `pandoc.lua` to data files.
* Add private module Text.Pandoc.Lua.PandocModule to supply the default lua module.
* Add Tests.Lua to tests.
* Add data/pandoc.lua, the lua module pandoc imports when processing its lua filters.
* Document in MANUAL.txt.
