Module:Transclude TOC

require('strict');

--[=[-< R E M O V E _ W I K I _ L I N K >--

Gets the display text from a wikilink like A|B or B gives B

The str:gsub returns either A|B froma A|B or B from B or B from B (no wikilink markup).

In l, l:gsub removes the link and pipe (if they exist); the second :gsub trims white space from the label if str was wrapped in wikilink markup. Presumably, this is because without wikimarkup in str, there is no match in the initial gsub, the replacement function l doesn't get called.

]=]

local function remove_wiki_link (str) return (str:gsub( "%[%[:?([^%[%]]*)%]%]", function(l) return l:gsub( "^[^|]*|(.*)$", "%1" ):gsub("^%s*(.-)%s*$", "%1"); end)); end

--[=[-< M A K E _ W I K I L I N K >

Makes a wikilink; when both link and display text is provided, returns a wikilink in the form L|D; if only link is provided, returns a wikilink in the form L; if neither are provided or link is omitted, returns an empty string.

]=]

local function make_wikilink (link, display) if link and ('' ~= link) then if display and ('' ~= display) then return table.concat ({, display, }); else return table.concat ({, link, }); end end return display or '';													-- link not set so return the display text end

--[[--< T O C >--

module entry point

create a wikilinked list of 's sections

]]

local function TOC (frame) local A = {};																-- table to hold section names and sizes local section_name_list = {}												-- an interim list that holds just the section names local section_content;														-- section content used for counting local section = '_LEAD_';													-- lead section doen't have a heading local count;																-- number of bytes in a section including the header text local _;																	-- dummy for using gsub to count bytes local lang = mw.language.getContentLanguage;								-- language object for number formatting appropriate to local language local s;																	-- start position of found heading (returned from string.find) local e = 1;																-- end position of found heading (returned from string.find) local section_name;															-- captured heading name (returned from string.find) local level;																-- number of leading '=' in heading markup; used for indenting subsections in the rendered list local wl_name;																-- anchor and display portion for wikilinks in rendered list

local title = mw.title.new (frame.args[1]);									-- page title local content = title:getContent;											-- get unparsed wikitext from the article if not content then return ' error: no article:' .. frame.args[1] .. ' ';	end

if title.isRedirect then													-- redirects don't have sections return ' error: ' .. frame.args[1] .. ' is a redirect '; end

section_content = content:match ('(.-)===*');								-- get the lead section if section_content then _, count = section_content:gsub ('.', '%1');							-- count the size of the lead section else return ' error: no sections found in: ' .. frame.args[1] .. ' ';	end table.insert (A, make_wikilink (frame.args[1], section));

while (1) do																-- done this way because some articles reuse section names s, e, section_name = string.find (content, '\n==+ *(.-) *==+', e);		-- get start, end, and section name beginning a end of last find; newline must precede '==' heading markup if s then table.insert (section_name_list, {section_name, s});				-- save section name and start location of this find else break; end end for i, section_name in ipairs (section_name_list) do		local escaped_section_name = string.gsub (section_name[1], '([%(%)%.%%%+%-%*%?%[%^%$%]])', '%%%1');	-- escape lua patterns in section name local pattern = '(==+ *' .. escaped_section_name .. ' *==+.-)==+';		-- make a pattern to get the content of a section section_content = string.match (content, pattern, section_name[2]);		-- get the content beginning at the string.find start location if section_content then _, count = section_content:gsub ('.', '%1');						-- count the bytes in the section else																	-- probably the last section (no proper header follows this section name) pattern = '(==+ *' .. escaped_section_name .. ' *==+.+)';			-- make a new pattern section_content = string.match (content, pattern, section_name[2]);	-- try to get content if section_content then _, count = section_content:gsub ('.', '%1');					-- count the bytes in the section else count = '—';													-- no content so show that end end

_, level = section_content:find ('^=+');								-- should always be the first n characters of section content level = (2 < level) and ((level-2) * 1.6) or nil;						-- remove offset and mult by 1.6em (same indent as ':' markup which doesn't work in a table)

wl_name = remove_wiki_link (section_name[1]):gsub ('%b{}', '');			-- remove wikilinks and templates from section headings so that we can link to the section wl_name = wl_name:gsub ('[%[%]]', {['[']='&#91;', [']']='&#93;'});		-- replace '[' and ']' characters with html entities so that wikilinked section names work wl_name = mw.text.trim (wl_name);										-- trim leading/trailing white space if any because white space buggers up url anchor links table.insert (A, table.concat ({										-- build most of a table row here because here we have heading information that we won't have later level and ' ' or '';		-- indent per heading level (number of '=' in heading markup) make_wikilink (frame.args[1] .. '#' .. wl_name, wl_name),			-- section link level and ' ' or ''}));										-- close the span if opened end

local out = {};																-- make a sortable wikitable for output table.insert (out, string.format ('{| class="wikitable" style="%s"\n|+Full table of contents for %s (%d sections)', frame.args.style or '', frame.args[1], #A));	-- output table header table.insert (out, '\n!Sections\n|-\n|');									-- column headers, and first row pipe table.insert (out, table.concat (A, '\n|-\n|'));							-- section rows with leading pipes (except first row already done) table.insert (out, '\n|}');													-- close the wikitable return table.concat (out, ''); end

----< E X P O R T E D  F U N C T I O N S >--

return {	TOC = TOC, }