1 files changed, 70 insertions, 0 deletions
diff --git a/paper/lua-filters/spellcheck/spellcheck.lua b/paper/lua-filters/spellcheck/spellcheck.lua
new file mode 100644
index 0000000..85ae281
--- /dev/null
+++ b/paper/lua-filters/spellcheck/spellcheck.lua
@@ -0,0 +1,70 @@
+-- lua filter for spell checking: requires 'aspell'.
+-- Copyright (C) 2017-2019 John MacFarlane, released under MIT license
+
+local text = require('text')
+local words = {}
+local deflang
+
+local function add_to_dict(lang, t)
+  if not words[lang] then
+    words[lang] = {}
+  end
+  if not words[lang][t] then
+    words[lang][t] = (words[lang][t] or 0) + 1
+  end
+end
+
+local function get_deflang(meta)
+  deflang = (meta.lang and meta.lang[1] and meta.lang[1].c) or 'en'
+  -- the following is better but won't work in pandoc 2.0.6.
+  -- it requires pandoc commit ecc46e229fde934f163d1f646383d24bfe2039e1:
+  -- deflang = (meta.lang and pandoc.utils.stringify(meta.lang)) or 'en'
+  return {} -- eliminate meta so it doesn't get spellchecked
+end
+
+local function run_spellcheck(lang)
+  local keys = {}
+  local wordlist = words[lang]
+  for k,_ in pairs(wordlist) do
+    keys[#keys + 1] = k
+  end
+  local inp = table.concat(keys, '\n')
+  local outp = pandoc.pipe('aspell', {'list','-l',lang}, inp)
+  for w in string.gmatch(outp, "(%a*)\n") do
+    io.write(w)
+    if lang ~= deflang then
+      io.write("\t[" .. lang .. "]")
+    end
+    io.write("\n")
+  end
+end
+
+local function results(el)
+    pandoc.walk_block(pandoc.Div(el.blocks), {Str = function(e) add_to_dict(deflang, e.text) end})
+    for lang,v in pairs(words) do
+        run_spellcheck(lang)
+    end
+    os.exit(0)
+end
+
+local function checkstr(el)
+  add_to_dict(deflang, el.text)
+end
+
+local function checkspan(el)
+  local lang = el.attributes.lang
+  if not lang then return nil end
+  pandoc.walk_inline(el, {Str = function(e) add_to_dict(lang, e.text) end})
+  return {} -- remove span, so it doesn't get checked again
+end
+
+local function checkdiv(el)
+  local lang = el.attributes.lang
+  if not lang then return nil end
+  pandoc.walk_block(el, {Str = function(e) add_to_dict(lang, e.text) end})
+  return {} -- remove div, so it doesn't get checked again
+end
+
+return {{Meta = get_deflang},
+        {Div = checkdiv, Span = checkspan},
+        {Str = function(e) add_to_dict(deflang, e.text) end, Pandoc = results}}