local p = {} local mRedirect = require('Module:Redirect')  -- Get a redirect target (or nil if not a redirect) without using the expensive title object property .isRedirect local function getRedirectTarget(titleObject)  local content = titleObject:getContent()  if not content then return nil end  return mRedirect.getTargetFromText(content) end  local errors -- Return blank text, or an error message if requested local function err(text)  if errors then error(text, 2) end  return "" end  -- In text, match pre..list[1]..post or pre..list[2]..post or ... local function matchany(text, pre, list, post)  local match  for i = 1, #list do  match = mw.ustring.match(text, pre .. list[i] .. post)  if match then return match end  end  return nil end  -- Get a page's content, following redirects, and processing file description pages for files. -- Also returns the page name, or the target page name if a redirect was followed, or false if no page found local function getContent(page, frame)  local title = mw.title.new(page) -- Read description page (for :File:Foo rather than File:Foo)  if not title then return false, false end   local redir = getRedirectTarget(title)  if redir then title = mw.title.new(redir) end   if title.namespace == 6 then  frame = frame or mw.getCurrentFrame()  return frame:preprocess("{{" .. title.prefixedText .. "}}"), redir or title.prefixedText  else  return title:getContent(), redir or title.prefixedText  end end  -- Check image for suitability local function checkimage(image)  local page = matchany(image, "", {"[Ff]ile", "[Ii]mage"}, "%s*:[^|%]]*") -- match File:(name) or Image:(name)  if not page then return false end   -- Limit to image types: .gif, .jpg, .jpeg, .png, .svg, .tiff, .xcf (exclude .ogg audio etc.)  if not matchany(page, "%.", {"[Gg][Ii][Ff]", "[Jj][Pp][Ee]?[Gg]", "[Pp][Nn][Gg]", "[Ss][Vv][Gg]", "[Tt][Ii][Ff][Ff]", "[Xx][Cc][Ff]"}, "%s*$") then  return false  end   local desc = getContent(page)  return ( desc and desc ~= "" and not mw.ustring.match(desc, "[Nn]on%-free") ) and true or false -- hide non-free image end  -- Attempt to parse [[File:...]] or [[Image:...]], either anywhere (start=false) or at the start only (start=true) local function parseimage(text, start)  local startre = ""  if start then startre = "^" end -- a true flag restricts search to start of string  local image = matchany(text, startre .. "%[%[%s*", {"[Ff]ile", "[Ii]mage"}, "%s*:.*") -- [[File: or [[Image: ...  if image then  image = mw.ustring.match(image, "%b[]%s*") -- matching [[...]] to handle wikilinks nested in caption  end  return image end  -- Parse a caption, which ends at a | (end of parameter) or } (end of infobox) but may contain nested [..] and {..} local function parsecaption(caption)  if not caption then return nil end  local len = mw.ustring.len(caption)  local pos = 1  while pos <= len do  local linkstart, linkend = mw.ustring.find(caption, "%b[]", pos)  linkstart = linkstart or len + 1 -- avoid comparison with nil when no link  local templatestart, templateend = mw.ustring.find(caption, "%b{}", pos)  templatestart = templatestart or len + 1 -- avoid comparison with nil when no template  local argend = mw.ustring.find(caption, "[|}]", pos) or len + 1  if linkstart < templatestart and linkstart < argend then  pos = linkend + 1 -- skip wikilink  elseif templatestart < argend then  pos = templateend + 1 -- skip template  else -- argument ends before the next wikilink or template  return mw.ustring.sub(caption, 1, argend - 1)  end  end end  -- Attempt to construct a [[File:...]] block from {{infobox ... |image= ...}} local function argimage(text)  local token = nil  local hasNamedArgs = mw.ustring.find(text, "|") and mw.ustring.find(text, "=")  if not hasNamedArgs then return nil end -- filter out any template that obviously doesn't contain an image   -- ensure image map is captured  text = mw.ustring.gsub(text, '<!%-%-imagemap%-%->', '|imagemap=')   -- find all images  local hasImages = false  local images = {}  local capture_from = 1  while capture_from < mw.ustring.len(text) do  local argname, position, image = mw.ustring.match(text, "|%s*([^=|]-[Ii][Mm][Aa][Gg][Ee][^=|]-)%s*=%s*()(.*)", capture_from)  if image then -- ImageCaption=, image_size=, image_upright=, etc. do not introduce an image  local lcArgname = mw.ustring.lower(argname)  if mw.ustring.find(lcArgname, "caption")  or mw.ustring.find(lcArgname, "size")  or mw.ustring.find(lcArgname, "upright") then  image = nil  end  end  if image then  hasImages = true  images[position] = image  capture_from = position  else  capture_from = mw.ustring.len(text)  end  end  capture_from = 1  while capture_from < mw.ustring.len(text) do  local position, image = mw.ustring.match(text, "|%s*[^=|]-[Pp][Hh][Oo][Tt][Oo][^=|]-%s*=%s*()(.*)", capture_from)  if image then  hasImages = true  images[position] = image  capture_from = position  else  capture_from = mw.ustring.len(text)  end  end  capture_from = 1  while capture_from < mw.ustring.len(text) do  local position, image = mw.ustring.match(text, "|%s*[^=|{}]-%s*=%s*()%[?%[?([^|{}]*%.%a%a%a%a?)%s*%f[|}]", capture_from)  if image then  hasImages = true  if not images[position] then  images[position] = image  end  capture_from = position  else  capture_from = mw.ustring.len(text)  end  end   if not hasImages then return nil end   -- find all captions  local captions = {}  capture_from = 1  while capture_from < mw.ustring.len(text) do  local position, caption = mw.ustring.match(text, "|%s*[^=|]*[Cc][Aa][Pp][Tt][Ii][Oo][Nn][^=|]*%s*=%s*()([^\n]+)", capture_from)  if caption then  -- extend caption to parse "| caption = Foo {{Template\n on\n multiple lines}} Bar\n"  local bracedCaption = mw.ustring.match(text, "^[^\n]-%b{}[^\n]+", position);  if bracedCaption and bracedCaption ~= "" then caption = bracedCaption end  caption = mw.text.trim(caption)  local captionStart = mw.ustring.sub(caption, 1, 1)  if captionStart == '|' or captionStart == '}' then caption = nil end  end  if caption then  -- find nearest image, and use same index for captions table  local i = position  while i > 0 and not images[i] do  i = i - 1  if images[i] then  if not captions[i] then  captions[i] = parsecaption(caption)  end  end  end  capture_from = position  else  capture_from = mw.ustring.len(text)  end  end   -- find all alt text  local altTexts = {}  for position, altText in mw.ustring.gmatch(text, "|%s*[Aa][Ll][Tt]%s*=%s*()([^\n]*)") do  if altText then  altText = mw.text.trim(altText)  local altTextStart = mw.ustring.sub(altText, 1, 1)  if altTextStart == '|' or altTextStart == '}' then altText = nil end  end  if altText then  -- find nearest image, and use same index for altTexts table  local i = position  while i > 0 and not images[i] do  i = i - 1  if images[i] then  if not altTexts[i] then  altTexts[i] = altText  end  end  end  end  end   -- find all image sizes  local imageSizes = {}  for position, imageSizeMatch in mw.ustring.gmatch(text, "|%s*[Ii][Mm][Aa][Gg][Ee][ _]?[Ss][Ii][Zz][Ee]%s*=%s*()([^}|\n]*)") do  local imageSize = mw.ustring.match(imageSizeMatch, "=%s*([^}|\n]*)")  if imageSize then  imageSize = mw.text.trim(imageSize )  local imageSizeStart = mw.ustring.sub(imageSize, 1, 1)  if imageSizeStart == '|' or imageSizeStart == '}' then imageSize = nil end  end  if imageSize then  -- find nearest image, and use same index for imageSizes table  local i = position  while i > 0 and not images[i] do  i = i - 1  if images[i] then  if not imageSizes[i] then  imageSizes[i] = imageSize  end  end  end  end  end   -- sort the keys of the images table (in a table sequence), so that images can be iterated over in order  local keys = {}  for key, val in pairs(images) do  table.insert(keys, key)  end  table.sort(keys)   -- add in relevant optional parameters for each image: caption, alt text and image size  local imageTokens = {}  for _, index in ipairs(keys) do  local image = images[index]  local token = parseimage(image, true) -- look for image=[[File:...]] etc.  if not token then  image = mw.ustring.match(image, "^[^}|\n]*") -- remove later arguments  token = "[[" -- Add File: unless name already begins File: or Image:  if not matchany(image, "^", {"[Ff]ile", "[Ii]mage"}, "%s*:") then  token = token .. "File:"  end  token = token .. image  local caption = captions[index]  if caption and mw.ustring.match(caption, "%S") then token = token .. "|" .. caption end  local alt = altTexts[index]  if alt then token = token .. "|alt=" .. alt end  local image_size = imageSizes[index]  if image_size and mw.ustring.match(image_size, "%S") then token = token .. "|" .. image_size end  token = token .. "]]"  end  token = mw.ustring.gsub(token, "\n","") .. "\n"  table.insert(imageTokens, token)  end  return imageTokens end  -- Help gsub convert imagemaps into standard images local function convertImagemap(imagemap)  local image = matchany(imagemap, "[>\n]%s*", {"[Ii]mage:", "[Ff]ile:"}, "[^\n]*")  if image then  return "<!--imagemap-->[[" .. mw.ustring.gsub(image, "[>\n]%s*", "", 1) .. "]]"  else  return "" -- remove entire block if image can't be extracted  end end  -- Help gsub to remove unwanted templates local function striptemplate(t)  -- If template is unwanted then return "" (gsub will replace by nothing), else return nil (gsub will keep existing string)  local unwanted = {"[Ee]fn", "[Ee]fn%-[lu][arg]", "[Ee]l[mn]", "[Rr]p?", "[Ss]fn[bmp]", "[Ss]f[bn]", "NoteTag", "#[Tt]ag:%s*[Rr]ef", "[Rr]efn?",  "[CcDd]n", "[Cc]itation needed", "[Dd]isambiguation needed", "[Ff]eatured article", "[Gg]ood article",  "[Dd]ISPLAYTITLE", "[Ss]hort[ _]+description", "[Cc]itation", "[Cc]ite[%- _]+[%w_%s]-", "[Cc]oor[%w_%s]-",  "[Uu]?n?[Rr]eliable source[%?%w_%s]-", "[Rr]s%??", "[Vv]c", "[Vv]erify credibility",  -- aliases for Clarification needed  "[Cc]f[ny]", "[Cc]larification[ _]+inline", "[Cc]larification[%- _]*needed", "[Cc]larification", "[Cc]larify%-inline", "[Cc]larify%-?me",  "[Cc]larify[ _]+inline", "[Cc]larify", "[Cc]LARIFY", "[Cc]onfusing%-inline", "[Cc]onfusing%-short", "[Ee]xplainme", "[Hh]uh[ _]*%??", "[Ww]hat%?",  "[Ii]nline[ _]+[Uu]nclear", "[Ii]n[ _]+what[ _]+sense", "[Oo]bscure", "[Pp]lease[ _]+clarify", "[Uu]nclear[ _]+inline", "[Ww]hat's[ _]+this%?",  "[Gg]eoQuelle",  -- Primary source etc.  "[Pp]s[ci]", "[Nn]psn", "[Nn]on%-primary[ _]+source[ _]+needed", "[Ss]elf%-published[%w_%s]-", "[Uu]ser%-generated[%w_%s]-",  "[Pp]rimary source[%w_%s]-", "[Ss]econdary source[%w_%s]-", "[Tt]ertiary source[%w_%s]-", "[Tt]hird%-party[%w_%s]-",  -- aliases for Disambiguation (page) and similar  "[Bb]egriffsklärung", "[Dd][Aa][Bb]", "[Dd]big", "[%w_%s]-%f[%w][Dd]isam[%w_%s]-", "[Hh][Nn][Dd][Ii][Ss]",  -- aliases for Failed verification  "[Bb]adref", "[Ff]aile?[ds] ?[rv][%w_%s]-", "[Ff][Vv]", "[Nn][Ii]?[Cc][Gg]", "[Nn]ot ?in ?[crs][%w_%s]-", "[Nn]ot specifically in source",  "[Vv]erification[%- _]failed",  -- aliases for When  "[Aa]s[ _]+of[ _]+when%??", "[Aa]s[ _%-]+of%??", "[Cc]larify date", "[Dd]ate[ _]*needed", "[Nn]eeds?[ _]+date", "[Rr]ecently", "[Ss]ince[ _]+when%??",  "[Ww]HEN", "[Ww]hen%??"}   if matchany(t, "^{{%s*", unwanted, "%s*%f[|}]") then return "" end   -- If template is wanted but produces an unwanted reference then return the string with |shortref or |ref removed  local noref = mw.ustring.gsub(t, "|%s*shortref%s*%f[|}]", "")  noref = mw.ustring.gsub(noref, "|%s*ref%s*%f[|}]", "")   -- If a wanted template has unwanted nested templates, purge them too  noref = mw.ustring.sub(noref, 1, 2) .. mw.ustring.gsub(mw.ustring.sub(noref, 3), "%b{}", striptemplate)  if noref ~= t then return noref end   return nil -- not an unwanted template: keep end  -- Convert a comma-separated list of numbers or min-max ranges into a list of booleans, e.g. "1,3-5" → {1=true,2=false,3=true,4=true,5=true} local function numberflags(str)  local ranges = mw.text.split(str, ",") -- parse ranges, e.g. "1,3-5" → {"1","3-5"}  local flags = {}  for _, r in pairs(ranges) do  local min, max = mw.ustring.match(r, "^%s*(%d+)%s*%-%s*(%d+)%s*$") -- "3-5" → min=3 max=5  if not max then min, max = mw.ustring.match(r, "^%s*((%d+))%s*$") end -- "1" → min=1 max=1  if max then  for p = min, max do flags[p] = true end  end  end  return flags end  -- a basic parser to trim down extracted wikitext -- @param text : Wikitext to be processed -- @param options : A table of options... -- options.paraflags : Which number paragraphs to keep, as either a string (e.g. `1,3-5`) or a table (e.g. `{1=true,2=false,3=true,4=true,5=true}`. If not present, all paragraphs will be kept. -- options.fileflags : table of which files to keep, as either a string (e.g. `1,3-5`) or a table (e.g. `{1=true,2=false,3=true,4=true,5=true}` -- options.fileargs : args for the [[File:]] syntax, such as `left` -- @param filesOnly : If set, only return the files and not the prose local function parse(text, options, filesOnly)  local allparas = true -- keep all paragraphs?  if options.paraflags then  if type(options.paraflags) ~= "table" then options.paraflags = numberflags(options.paraflags) end  for _, v in pairs(options.paraflags) do  if v then allparas = false end -- if any para specifically requested, don't keep all  end  end  if filesOnly then  allparas = false  options.paraflags = {}  end   local maxfile = 0 -- for efficiency, stop checking images after this many have been found  if options.fileflags then  if type(options.fileflags) ~= "table" then options.fileflags = numberflags(options.fileflags) end  for k, v in pairs(options.fileflags) do  if v and k > maxfile then maxfile = k end -- set maxfile = highest key in fileflags  end  end   local fileargs = options.fileargs and mw.text.trim(options.fileargs)  if fileargs == '' then fileargs = nil end   local leadstart = nil -- have we found some text yet?  local t = "" -- the stripped down output text  local filetext = "" -- output text with concatenated [[File:Foo|...]]\n entries  local files = 0 -- how many images so far  local paras = 0 -- how many paragraphs so far  local startLine = true -- at the start of a line (no non-spaces found since last \n)?   text = mw.ustring.gsub(text,"^%s*","") -- remove initial white space  repeat -- loop around parsing a template, image or paragraph  local token = mw.ustring.match(text, "^%b{}%s*") or false -- {{Template}}  local line = mw.ustring.match(text, "[^\n]*")  if token and line and mw.ustring.len(token) < mw.ustring.len(line) then -- template is followed by text (but it may just be other templates)  line = mw.ustring.gsub(line, "%b{}", "") -- remove all templates from this line  -- if anything is left, other than an incomplete further template or an image, keep the template: it counts as part of the line  if mw.ustring.find(line, "%S") and not matchany(line, "^%s*", { "{{", "%[%[%s*[Ff]ile:", "%[%[%s*[Ii]mage:" }, "") then  token = nil  end  end   if token then -- found a template which is not the prefix to a line of text  if leadstart then -- lead has already started, so keep the template within the text, unless it's a whole line (navbox etc.)  if not filesOnly and not startLine then t = t .. token end  elseif files < maxfile then -- discard template, but if we are still collecting images...  local images = argimage(token) or {}  if not images then  local image = parseimage(token, false) -- look for embedded [[File:...]], |image=, etc.  if image then table.insert(images, image) end  end  for _, image in ipairs(images) do  if files < maxfile and checkimage(image) then -- if image is found and qualifies (not a sound file, non-free, etc.)  files = files + 1 -- count the file, whether displaying it or not  if options.fileflags and options.fileflags[files] then -- if displaying this image  image = mw.ustring.gsub(image, "|%s*frameless%s*%f[|%]]", "") -- make image a thumbnail, not frameless etc.  image = mw.ustring.gsub(image, "|%s*framed?%s*%f[|%]]", "")  if not matchany(image, "|%s*", {"thumb", "thumbnail"}, "%s*%f[|%]]") then  image = mw.ustring.gsub(image, "(%]%]%s*)$", "|thumb%1")  end  if fileargs then image = mw.ustring.gsub(image, "(%]%]%s*)$", "|" .. fileargs .. "%1") end  filetext = filetext .. image  end  end  end  end  else -- the next token in text is not a template  token = parseimage(text, true)  if token then -- the next token in text looks like an image  if files < maxfile and checkimage(token) then -- if more images are wanted and this is a wanted image  files = files + 1  if options.fileflags and options.fileflags[files] then  local image = token -- copy token for manipulation by adding |right etc. without changing the original  if fileargs then image = mw.ustring.gsub(image, "(%]%]%s*)$", "|" .. fileargs .. "%1") end  filetext = filetext .. image  end  end  else -- got a paragraph, which ends at a file, image, blank line or end of text  local afterend = mw.ustring.len(text) + 1  local blankpos = mw.ustring.find(text, "\n%s*\n") or afterend -- position of next paragraph delimiter (or end of text)  local endpos = math.min( -- find position of whichever comes first: [[File:, [[Image: or paragraph delimiter  mw.ustring.find(text, "%[%[%s*[Ff]ile%s*:") or afterend,  mw.ustring.find(text, "%[%[%s*[Ii]mage%s*:") or afterend,  blankpos)  token = mw.ustring.sub(text, 1, endpos-1)  if blankpos < afterend and blankpos == endpos then -- paragraph ends with a blank line  token = token .. mw.ustring.match(text, "\n%s*\n", blankpos)  end  leadstart = leadstart or mw.ustring.len(t) + 1 -- we got a paragraph, so mark the start of the lead section  paras = paras + 1  if allparas or (options.paraflags and options.paraflags[paras]) then t = t .. token end -- add if this paragraph wanted  end -- of "else got a paragraph"  end -- of "else not a template"   if token then text = mw.ustring.sub(text, mw.ustring.len(token)+1) end -- remove parsed token from remaining text  startLine = mw.ustring.find(token, "\n%s*$"); -- will the next token be the first non-space on a line?  until not text or text == "" or not token or token == "" -- loop until all text parsed   text = mw.ustring.gsub(filetext .. t, "\n+$", "") -- remove trailing line feeds, so "{{Transclude text excerpt|Foo}} more" flows on one line  return text, leadstart end  local function cleanupText(text, leadOnly)  text = mw.ustring.gsub(text, "<!%-%-.-%-%->","") -- remove HTML comments  if leadOnly then  text = mw.ustring.gsub(text, "%c%s*==.*","") -- remove first ==Heading== and everything after it  end  text = mw.ustring.gsub(text, "<noinclude>.-</noinclude>", "") -- remove noinclude bits  text = mw.ustring.gsub(text, "<%s*[Rr]ef[^>]-/%s*>", "") -- remove refs cited elsewhere  text = mw.ustring.gsub(text, "<%s*[Rr]ef.->.-<%s*/%s*ref%s*>", "") -- remove refs  text = mw.ustring.gsub(text, "<%s*[Ii]magemap.->.-<%s*/%s*imagemap%s*>", convertImagemap) -- convert imagemaps into standard images  text = mw.ustring.gsub(text, "%b{}", striptemplate) -- remove unwanted templates such as references  text = mw.ustring.gsub(text, "%s*{{%s*[Tt][Oo][Cc].-}}", "") -- remove most common tables of contents  text = mw.ustring.gsub(text, "%s*__[A-Z]*TOC__", "") -- remove TOC behavior switches  text = mw.ustring.gsub(text, "\n%s*{{%s*[Pp]p%-.-}}", "\n") -- remove protection templates  text = mw.ustring.gsub(text, "%s*{{[^{|}]*[Ss]idebar%s*}}", "") -- remove most sidebars  text = mw.ustring.gsub(text, "%s*{{[^{|}]*%-[Ss]tub%s*}}", "") -- remove most stub templates  text = mw.ustring.gsub(text, "%s*%[%[%s*:?[Cc]ategory:.-%]%]", "") -- remove categories  text = mw.ustring.gsub(text, "^:[^\n]+\n","") -- remove DIY hatnote indented with a colon  return text end  -- Parse a ==Section== from a page local function getsection(text, section, mainonly)  local level, content = mw.ustring.match(text .. "\n", "\n(==+)%s*" .. section .. "%s*==.-\n(.*)")  if not content then return nil end -- no such section  local nextsection  if mainonly then  nextsection = "\n==.*" -- Main part of section terminates at any level of header  else  nextsection = "\n==" .. mw.ustring.rep("=?", #level - 2) .. "[^=].*" -- "===" → "\n===?[^=].*", matching "==" or "===" but not "===="  end  content = mw.ustring.gsub(content, nextsection, "") -- remove later sections with headings at this level or higher  return content end  -- Main function returns a string value: text of the lead of a page local function main(pagenames, options)  if not pagenames or #pagenames < 1 then return err("No page names given") end  local pagename  local text  local pagecount = #pagenames  local firstpage = pagenames[1] or "(nil)" -- save for error message, as it the name will be deleted   -- read the page, or a random one if multiple pages were provided  if pagecount > 1 then math.randomseed(os.time()) end  while not text and pagecount > 0 do  local pagenum = 1  if pagecount > 1 then pagenum = math.random(pagecount) end -- pick a random title  pagename = pagenames[pagenum]  if pagename and pagename ~= "" then  pagename = mw.ustring.match(pagename, "%[%[%s*(.-)[%]|]") or pagename -- "[[Foo|Bar]]" → "Foo"  pagename = mw.ustring.gsub(pagename, "^%s+", "") -- strip leading ...  pagename = mw.ustring.gsub(pagename, "%s+$", "") -- ...and trailing white space   if pagename and pagename ~= "" then  local pn, section = mw.ustring.match(pagename, "(.-)#(.*)")  pagename = pn or pagename  text, normalisedPagename = getContent(pagename)  if not normalisedPagename then  return err("No title for page name " .. pagename)  else  pagename = normalisedPagename  end  if text and options.nostubs then  local isStub = mw.ustring.find(text, "%s*{{[^{|}]*%-[Ss]tub%s*}}")  if isStub then text = nil end  end  if not section then  section = mw.ustring.match(pagename, ".-#(.*)") -- parse redirect to Page#Section  end  if text and section then text = getsection(text, section) end  end  end  if not text then table.remove(pagenames, pagenum) end -- this one didn't work; try another  pagecount = pagecount - 1 -- ensure that we exit the loop after at most #pagenames iterations  end  if not text then return err("Cannot read a valid page: first name is " .. firstpage) end   text = cleanupText(text, true)  text, leadstart = parse(text, options)   -- replace the bold title or synonym near the start of the article by a wikilink to the article  local lang = mw.language.getContentLanguage()  local pos = mw.ustring.find(text, "'''" .. lang:ucfirst(pagename) .. "'''", 1, true) -- look for "'''Foo''' is..." (uc) or "A '''foo''' is..." (lc)  or mw.ustring.find(text, "'''" .. lang:lcfirst(pagename) .. "'''", 1, true) -- plain search: special characters in pagename represent themselves  if pos then  local len = mw.ustring.len(pagename)  text = mw.ustring.sub(text, 1, pos + 2) .. "[[" .. mw.ustring.sub(text, pos + 3, pos + len + 2) .. "]]" .. mw.ustring.sub(text, pos + len + 3, -1) -- link it  else -- look for anything unlinked in bold, assumed to be a synonym of the title (e.g. a person's birth name)  text = mw.ustring.gsub(text, "(.-''')(.-'*)'''", function(a, b)  if mw.ustring.len(a) < 100 + (leadstart or 0) and not mw.ustring.find(b, "%[") then ---if early in article and not wikilinked  return a .. "[[" .. pagename .. "|" .. b .. "]]'''" -- replace '''Foo''' by '''[[pagename|Foo]]  else  return nil -- instruct gsub to make no change  end  end, 1) -- "end" here terminates the anonymous replacement function(a, b) passed to gsub  end   if options.more then text = text .. " '''[[" .. pagename .. "|" .. options.more .. "]]'''" end -- wikilink to article for more info  return text end  -- Shared template invocation code for lead and random functions local function invoke(frame, func)  -- args = { 1,2,... = page names, paragraphs = list e.g. "1,3-5", files = list, more = text}  local args = {} -- args[k] = frame.args[k] or frame:getParent().args[k] for all k in either (numeric or not)  for k, v in pairs(frame:getParent().args) do args[k] = v end  for k, v in pairs(frame.args) do args[k] = v end -- args from a Lua call have priority over parent args from template  errors = args["errors"] -- set the module level boolean used in local function err   local articlecount = #args -- must be 1 except with selected=Foo and Foo=Somepage  if articlecount < 1 and not (func == "selected" and args[func] and args[args[func]]) then  return err("No articles provided")  end   local pagenames = {}  if func == "lead" then  pagenames = { args[1] }  elseif func == "linked" or func == "listitem" then  -- Read named page and find its wikilinks  local page = args[1]  local text, title = getContent(page)  if not title then  return err("No title for page name " .. page)  elseif not text then  return err("No content for page name " .. page)  end  if args["section"] then -- check relevant section only  text = getsection(text, args["section"], args["sectiononly"])  if not text then return err("No section " .. args["section"] .. " in page " .. page) end  end  -- replace annotated links with real links  text = mw.ustring.gsub(text, "{{%s*[Aa]nnotated[ _]link%s*|%s*(.-)%s*}}", "[[%1]]")  if func == "linked" then  for p in mw.ustring.gmatch(text, "%[%[%s*([^%]|\n]*)") do table.insert(pagenames, p) end  else -- listitem: first wikilink on a line beginning *, :#, etc. except in "See also" or later section  text = mw.ustring.gsub(text, "\n== *See also.*", "")  for p in mw.ustring.gmatch(text, "\n:*[%*#][^\n]-%[%[%s*([^%]|\n]*)") do table.insert(pagenames, p) end  end  elseif func == "random" then  -- accept any number of page names. If more than one, we'll pick one randomly  for i, p in pairs(args) do  if p and type(i) == 'number' then table.insert(pagenames, p) end  end  elseif func == "selected" then  local articlekey = args[func]  if tonumber(articlekey) then -- normalise article number into the range 1..#args  articlekey = articlekey % articlecount  if articlekey == 0 then articlekey = articlecount end  end  pagenames = { args[articlekey] }  end   local options = args -- pick up miscellaneous options: more, errors, fileargs  options.paraflags = numberflags(args["paragraphs"] or "") -- parse paragraphs, e.g. "1,3-5" → {"1","3-5"}  options.fileflags = numberflags(args["files"] or "") -- parse file numbers  if options.more and options.more == "" then options.more = "Read more..." end -- more= is short for this default text   local text = main(pagenames, options)  return frame:preprocess(text) end  -- Entry points for template callers using #invoke: function p.lead(frame) return invoke(frame, "lead") end -- {{Transclude lead excerpt}} reads the first and only article function p.linked(frame) return invoke(frame, "linked") end -- {{Transclude linked excerpt}} reads a randomly selected article linked from the given page function p.listitem(frame) return invoke(frame, "listitem") end -- {{Transclude list item excerpt}} reads a randomly selected article listed on the given page function p.random(frame) return invoke(frame, "random") end -- {{Transclude random excerpt}} reads any article (default for invoke with one argument) function p.selected(frame) return invoke(frame, "selected") end -- {{Transclude selected excerpt}} reads the article whose key is in the selected= parameter  -- Entry points for other Lua modules function p.getContent(page, frame) return getContent(page, frame) end function p.getsection(text, section) return getsection(text, section) end function p.parse(text, options, filesOnly) return parse(text, options, filesOnly) end function p.argimage(text) return argimage(text) end function p.checkimage(image) return checkimage(image) end function p.parseimage(text, start) return parseimage(text, start) end function p.cleanupText(text, leadOnly) return cleanupText(text, leadOnly) end function p.main(pagenames, options) return main(pagenames, options) end function p.numberflags(str) return numberflags(str) end  return p