-- This module de-links most wikitext.  require('Module:No globals')  local p = {}  local getArgs  local function delinkReversePipeTrick(s)  if s:match("^%[%[|.*[|\n]") then -- Check for newlines or multiple pipes.  return s  else  return s:match("%[%[|(.*)%]%]")  end end  local function delinkPipeTrick(s)  local linkarea, display = "", ""  -- We need to deal with colons, brackets, and commas, per [[Help:Pipe trick]].   -- First, remove the text before the first colon, if any.  if s:match(":") then  s = s:match("%[%[.-:(.*)|%]%]")  -- If there are no colons, grab all of the text apart from the square brackets and the pipe.  else  s = s:match("%[%[(.*)|%]%]")  end   -- Next up, brackets and commas.  if s:match("%(.-%)$") then -- Brackets trump commas.  s = s:match("(.-) ?%(.-%)$")  elseif s:match(",") then -- If there are no brackets, display only the text before the first comma.  s = s:match("(.-),.*$")  end  return s end  local function delinkWikilink(s)  local result = s  -- Deal with the reverse pipe trick.  if result:match("%[%[|") then  return delinkReversePipeTrick(result)  end   result = mw.uri.decode(result, "PATH") -- decode percent-encoded entities. Leave underscores and plus signs.  result = mw.text.decode(result, true) -- decode HTML entities.   -- Check for bad titles. To do this we need to find the  -- title area of the link, i.e. the part before any pipes.  local titlearea  if result:match("|") then -- Find if we're dealing with a piped link.  titlearea = result:match("^%[%[(.-)|.*%]%]")  else  titlearea = result:match("^%[%[(.-)%]%]")  end  -- Check for bad characters.  if mw.ustring.match(titlearea, "[%[%]<>{}%%%c\n]") then  return s  end   -- Check for categories, interwikis, and files.  local colonprefix = result:match("%[%[(.-):.*%]%]") or "" -- Get the text before the first colon.  local ns = mw.site.namespaces[colonprefix] -- see if this is a known namespace  if mw.language.isKnownLanguageTag(colonprefix)  or ( ns and ( ns.canonicalName == "File" or ns.canonicalName == "Category" ) ) then  return ""  end   -- Remove the colon if the link is using the [[Help:Colon trick]].  if result:match("%[%[:") then  result = "[[" .. result:match("%[%[:(.*%]%])")  end   -- Deal with links using the [[Help:Pipe trick]].  if mw.ustring.match(result, "^%[%[[^|]*|%]%]") then  return delinkPipeTrick(result)  end   -- Find the display area of the wikilink  if result:match("|") then -- Find if we're dealing with a piped link.  result = result:match("^%[%[.-|(.+)%]%]")  -- Remove new lines from the display of multiline piped links,  -- where the pipe is before the first new line.  result = result:gsub("\n", "")  else  result = result:match("^%[%[(.-)%]%]")  end   return result end  local function delinkURL(s)  -- Assume we have already delinked internal wikilinks, and that  -- we have been passed some text between two square brackets [foo].   -- If the text contains a line break it is not formatted as a URL, regardless of other content.  if s:match("\n") then  return s  end   -- Check if the text has a valid URL prefix and at least one valid URL character.  local valid_url_prefixes = {"//", "http://", "https://", "ftp://", "gopher://", "mailto:", "news:", "irc://"}  local url_prefix  for i,v in ipairs(valid_url_prefixes) do  if mw.ustring.match(s, '^%[' .. v ..'[^"%s].*%]' ) then  url_prefix = v  break  end  end   -- Get display text  if not url_prefix then  return s  end  s = s:match("^%[" .. url_prefix .. "(.*)%]") -- Grab all of the text after the URL prefix and before the final square bracket.  s = s:match('^.-(["<> ].*)') or "" -- Grab all of the text after the first URL separator character ("<> ).  s = mw.ustring.match(s, "^%s*(%S.*)$") or "" -- If the separating character was a space, trim it off.   local s_decoded = mw.text.decode(s, true)  if mw.ustring.match(s_decoded, "%c") then  return s  else  return s_decoded  end end  local function delinkLinkClass(s, pattern, delinkFunction)  if not type(s) == "string" then  error("Attempt to de-link non-string input.", 2)  end  if not ( type(pattern) == "string" and mw.ustring.sub(pattern, 1, 1) == "^" ) then  error('Invalid pattern detected. Patterns must begin with "^".', 2)  end  -- Iterate over the text string, and replace any matched text. using the   -- delink function. We need to iterate character by character rather   -- than just use gsub, otherwise nested links aren't detected properly.  local result = ""  while s ~= '' do  -- Replace text using one iteration of gsub.  s = mw.ustring.gsub(s, pattern, delinkFunction, 1)  -- Append the left-most character to the result string.  result = result .. mw.ustring.sub(s, 1, 1)  s = mw.ustring.sub(s, 2, -1)  end  return result end  function p._delink(args)  local text = args[1] or ""  if args.refs == "yes" then  -- Remove any [[Help:Strip markers]] representing ref tags. In most situations   -- this is not a good idea - only use it if you know what you are doing!  text = mw.ustring.gsub(text, "UNIQ%w*%-ref%-%d*%-QINU", "")  end  if not (args.comments == "no") then  text = text:gsub("<!%-%-.-%-%->", "") -- Remove html comments.  end  if not (args.wikilinks == "no") then  text = delinkLinkClass(text, "^%[%[.-%]%]", delinkWikilink) -- De-link wikilinks.  end  if not (args.urls == "no") then  text = delinkLinkClass(text, "^%[.-%]", delinkURL) -- De-link URLs.  end  if not (args.whitespace == "no") then  -- Replace single new lines with a single space, but leave double new lines  -- and new lines only containing spaces or tabs before a second new line.  text = mw.ustring.gsub(text, "([^\n \t][ \t]*)\n([ \t]*[^\n \t])", "%1 %2")  text = text:gsub("[ \t]+", " ") -- Remove extra tabs and spaces.  end  return text end  function p.delink(frame)  if not getArgs then  getArgs = require('Module:Arguments').getArgs  end  return p._delink(getArgs(frame, {wrappers = 'Template:Delink'})) end  return p