Define heavyweight macros in a scripting language

[dhasenan]

Let's say I'm writing a novel about Zatanna Zatara from the DC universe. I want to define something to automatically generate her backwards-speech spell thing. I should be able to do that. Something like:

% main.sub
\loadscript{util.lua}
\chapter{}
\zataracast{mosquitos be gone}!

-- util.lua
function macro.zataracast(content)
  if content.type == text then
    text = ''
    for word of content.text:split(' ') do
      if text.length > 0 then text += ' ' end
      text += word:reverse()
    done
    content.text = text
  end
end

[dhasenan]

We'll provide a global variable for Lua to muck about with instead of using the module system. We should also be able to examine the defined functions, so if someone calls a defined function that isn't defined within the macro table, we can inform the user how to fix the mistake.