Module:Navseasoncats

local p = {}

--========================================================================== --                               Globals --==========================================================================

local currtitle = mw.title.getCurrentTitle local nexistingcats = 0 local errors = '' local testcasecolon = '' local testcases = string.match(currtitle.subpageText, '^testcases') if   testcases then testcasecolon = ':' end local navborder = true local followRs = true local skipgaps = false local listall = false local tlistall = {} local tlistallbwd = {} local tlistallfwd = {} local ttrackingcats = { --when reindexing, Ctrl+H 'trackcat(13,' & 'ttrackingcats[16]'	, -- [1] placeholder for 	, -- [2] placeholder for 	, -- [3] placeholder for 	, -- [4] placeholder for 	, -- [5] placeholder for 	, -- [6] placeholder for 	, -- [7] placeholder for --new	, -- [8] placeholder for 	, -- [9] placeholder for 	, --[10] placeholder for 	, --[11] placeholder for 	, --[12] placeholder for 	, --[13] placeholder for 	, --[14] placeholder for 	, --[15] placeholder for 	, --[16] placeholder for 	, --[17] placeholder for 	, --[18] placeholder for 	, --[19] placeholder for 	, --[20] placeholder for 	, --[21] placeholder for 	, --[22] placeholder for 	, --[23] placeholder for 	, --[24] placeholder for 	, --[25] placeholder for 	, --[26] placeholder for 	, --[27] placeholder for 	, --[28] placeholder for 	'', --[29] placeholder for '', --[30] placeholder for '', --[31] placeholder for } local avoidself = (not string.match(currtitle.text, 'Navseasoncats with') and					not string.match(currtitle.text, 'Navseasoncats.*/doc') and					not string.match(currtitle.text, 'Navseasoncats.*/sandbox') and					currtitle.text ~= 'Navseasoncats' and					currtitle.nsText ~= 'User_talk' and					currtitle.nsText ~= 'Template_talk' and					(currtitle.nsText ~= 'Template' or testcases)) --avoid nested transclusion errors (i.e. )

--========================================================================== --                     Utility & category functions --==========================================================================

--Determine if a category exists (in a function for easier localization). local function catexists( title ) return mw.title.new( title, 'Category' ).exists end

--Error message handling. function p.errorclass( msg ) return mw.text.tag( 'span', {class='error mw-ext-cite-error'}, 'Error! '..string.gsub(msg, '&#', '&amp;#') ) end

--Failure handling. function p.failedcat( errors, sortkey ) if avoidself then return (errors or '')..'&#42;&#42;&#42;Navseasoncats failed to generate navbox***'.. ''..(sortkey or 'O')..'\n' end return '' end

--Tracking cat handling. --	key: 15 (when reindexing ttrackingcats{}, Ctrl+H 'trackcat(13,' & 'ttrackingcats[16]') --	cat: 'Navseasoncats isolated';  to remove --Used by main, all nav_*, & several utility functions. local function trackcat( key, cat )	if avoidself and key and cat then		if cat ~=  then			ttrackingcats[key] = ..testcasecolon..'Category:'..cat..		else			ttrackingcats[key] = ''		end	end	return end

--Check for unknown parameters. --Used by main only. local function checkforunknownparams( tbl ) local knownparams = { ['min'] = 'min', ['max'] = 'max', ['cat'] = 'cat', ['testcase'] = 'testcase', ['testcasegap'] = 'testcasegap', ['skip-gaps'] = 'skip-gaps', ['list-all-links'] = 'list-all-links', ['follow-redirects'] = 'follow-redirects', }	for k, _ in pairs (tbl) do		if knownparams[k] == nil then trackcat(3, 'Navseasoncats using unknown parameter') break end end end

--Check for nav_* navigational isolation (not necessarily an error). --Used by all nav_*. local function isolatedcat if nexistingcats == 0 then trackcat(16, 'Navseasoncats isolated') end end

--Returns the target of, if it exists, else returns the original cat. --, etc., if found, are evaluated. --Used by catlinkfollowr, and so indirectly by all nav_*. local function rtarget( frame, cat ) local catcontent = mw.title.new( cat or '', 'Category' ):getContent if string.match( catcontent or '', '{{ *[Cc]at' ) then --prelim test local tregex = { --the following 11 pages (6 condensed) redirect to Template:Category redirect, in descending order, as of 9/2022: '{{ *[Cc]ate?g?o?r?y?[ _]*[rR]edirect',	--505+312+243+1 transclusions '{{ *[Cc]atr',							--21 '{{ *[Cc]at[ _]*[rR]edir',				--5+3 '{{ *[Cc]at[ _]*[rR]ed',				--3+2 '{{ *[Cc]at[ _]*[mM]ove',				--1 '{{ *[Cc]ategory[ _]*[mM]ove',			--0 }		for _, v in pairs (tregex) do			local rtarget = mw.ustring.match( catcontent, v..'%s*|%s*([^|}]+)' ) if rtarget then if string.match(rtarget, '{{') then --, etc., exists; evaluate local regex_ty = '%s*|%s*([^{}]*{{([^{|}]+)}}[^{}]-)%s*}}' --eval null-param templates only; expanded if/as needed local rtarget_orig, ty = mw.ustring.match( catcontent, v..regex_ty ) if rtarget_orig then local ty_eval = frame:expandTemplate{ title = ty, args = { page = cat } } --frame:newChild doesn't work, use 'page' param instead local rtarget_eval = mw.ustring.gsub(rtarget_orig, '{{%s*'..ty..'%s*}}', ty_eval ) return rtarget_eval else --sub-parameters present; track & return default trackcat(31, 'Navseasoncats redirection error') end end rtarget = mw.ustring.gsub(rtarget, '^1%s*=%s*', '') rtarget = string.gsub(rtarget, '^[Cc]ategory:', '') return rtarget end end --for end --if return cat end

--Similar to {{LinkCatIfExists2}}: make a piped link to a category, if it exists; --if it doesn't exist, just display the greyed link title without linking. --Follows s. --Returns { --			['cat'] = cat, --			['catexists'] = true, --			['rtarget'] = <#R target>, --			['navelement'] = <#R target navelement>, --			['displaytext'] = displaytext, --		 } if #R followed; --returns { --			['cat'] = cat, --			['catexists'] = , --			['rtarget'] = nil, --			['navelement'] = , --			['displaytext'] = displaytext, --		 } otherwise. --Used by all nav_*. local function catlinkfollowr( frame, cat, displaytext, displayend ) cat        = mw.text.trim(cat or '') displaytext = mw.text.trim(displaytext or '') displayend = displayend or false --bool flag to override displaytext IIF the cat/target is terminal (e.g. "2021–present" or "2021–") local grey = '#888' local disp = cat if displaytext ~= '' then --use 'displaytext' parameter if present disp = mw.ustring.gsub(displaytext, '%s+%(.+$', ); --strip any trailing disambiguator	end	local link, nilorR	local exists = catexists(cat)	if exists then		nexistingcats = nexistingcats + 1		if followRs then			local R = rtarget(frame, cat) --find & follow #R			if R ~= cat then --#R followed				nilorR = R			end			if displayend then				local y, hyph, ending = mw.ustring.match(R, '^.-(%d+)([–-])(.*)$')				if ending == 'present' then					disp = y..hyph..ending				elseif ending ==  then					disp = y..hyph..' '..y..' ' --hidden y to match spacing				end			end			link = ..disp..		else			link = ..disp..		end	else		link = ' '..disp..' '	end	if listall then		if nilorR then --#R followed			table.insert( tlistall, 'Category:'..cat..' → '..'Category:'..nilorR..' ('..link..')' )		else --no #R			table.insert( tlistall, 'Category:'..cat..' ('..link..')' ) end end return { ['cat'] = cat, ['catexists'] = exists, ['rtarget'] = nilorR, ['navelement'] = link, ['displaytext'] = disp, } end

--Returns a numbered list of all {{Category redirect}}s followed by catlinkfollowr -> rtarget. --For a nav_hyphen cat, also returns a formatted list of all cats searched for & found, & all loop indices. --Used by all nav_*. local function listalllinks local nl = '\n# ' local out = '' if currtitle.nsText == 'Category' then errors = p.errorclass('The   parameter/utility '..							'should not be saved in category space, only previewed.') out = p.failedcat(errors, 'Z') end local bwd, fwd = ,  if tlistallbwd[1] then bwd = '\n\nbackward search:\n# '..table.concat(tlistallbwd, nl) end if tlistallfwd[1] then fwd = '\n\nforward search:\n# '..table.concat(tlistallfwd, nl) end if tlistall[1] then return out..nl..table.concat(tlistall, nl)..bwd..fwd else return out..nl..'No links found!?'..bwd..fwd end end

--Returns the difference b/w 2 ints separated by endash|hyphen, nil if error. --Used by nav_hyphen only. local function find_duration( cat ) local from, to = mw.ustring.match(cat, '(%d+)[–-](%d+)') if from and to then if to == '00' then return nil end --doesn't follow MOS:DATERANGE if (#from == 4) and (#to == 2) then            --1900-01 to = string.match(from, '(%d%d)%d%d')..to  --1900-1901 elseif (#from == 2) and (#to == 4) then        --  01-1902 from = string.match(to, '(%d%d)%d%d')..from --1901-1902 end return (tonumber(to) - tonumber(from)) end return 0 end

--Returns the ending of a terminal cat, and sets the appropriate tracking cat, else nil. --Used by nav_hyphen only. local function find_terminaltxt( cat ) local terminaltxt = nil if mw.ustring.match(cat, '%d+[–-]present$') then terminaltxt = 'present' trackcat(14, 'Navseasoncats range ends (present)') elseif mw.ustring.match(cat, '%d+[–-]$') then terminaltxt = '' trackcat(15, 'Navseasoncats range ends (blank, MOS)') end return terminaltxt end

--Returns an unsigned string of the 1-4 digit decade ending in "0", else nil. --Used by nav_decade only. local function sterilizedec( decade ) if decade == nil or decade == '' then return nil end local dec = string.match(decade, '^[-%+]?(%d?%d?%d?0)$') or				string.match(decade, '^[-%+]?(%d?%d?%d?0)%D') if dec then return dec else --fix 2-4 digit decade local decade_fixed234 = string.match(decade, '^[-%+]?(%d%d?%d?)%d$') or								string.match(decade, '^[-%+]?(%d%d?%d?)%d%D') if decade_fixed234 then return decade_fixed234..'0' end --fix 1-digit decade local decade_fixed1  = string.match(decade, '^[-%+]?(%d)$') or								string.match(decade, '^[-%+]?(%d)%D') if decade_fixed1 then return '0' end --unfixable return nil end end

--Check for nav_hyphen default gap size + isolatedcat (not necessarily an error). --Used by nav_hyphen only. local function defaultgapcat( bool ) if bool and nexistingcats == 0 then --using "nexistingcats > 0" isn't as useful, since the default gap size obviously worked trackcat(17, 'Navseasoncats default season gap size') end end

--12 -> 12th, etc. --Used by nav_nordinal & nav_wordinal. function p.addord( i ) if tonumber(i) then local s = tostring(i) local tens = string.match(s, '1%d$') if   tens then return s..'th' end local ones = string.match(s, '%d$') if    ones == '1' then return s..'st' elseif ones == '2' then return s..'nd' elseif ones == '3' then return s..'rd' end return s..'th' end return i end

--Returns the properly formatted central nav element. --Expects an integer i, and a catlinkfollowr table. --Used by nav_decade & nav_ordinal only. local function navcenter( i, catlink ) if i == 0 then --center nav element if navborder == true then return '*'..catlink.displaytext..'\n' else return '*'..catlink.navelement..'\n' end else return '*'..catlink.navelement..'\n' end end

--Return conditionally aligned stacked navs. --Used by main only. local function nav1nav2( nav1, nav2 ) if avoidself then local forcealign = '' return forcealign..'\n'..nav1..'\n'..nav2..'\n ' else return nav1..'\n'..nav2 end end

--========================================================================== --                 Formerly separated templates/modules --==========================================================================

--==========================={{ nav_hyphen  }}=============================

local function nav_hyphen( frame, start, hyph, finish, firstpart, lastpart, minseas, maxseas, testgap ) --Expects a PAGENAME of the form "Some sequential 2015–16 example cat", where --	start    = 2015 --	hyph     = – --	finish   = 16 (sequential years can be abbreviated, but others should be full year, e.g. "2001–2005") --	firstpart = Some sequential --	lastpart = example cat --	minseas  = 1800 ('min' starting season shown; optional; defaults to -9999) --	maxseas  = 2000 ('max' starting season shown; optional; defaults to 9999; 2000 will show 2000-01) --	testgap  = 0 (testcasegap parameter for easier testing; optional) --sterilize start if string.match(start or '', '^%d%d?%d?%d?$') == nil then --1-4 digits, AD only local start_fixed = mw.ustring.match(start or '', '^%s*(%d%d?%d?%d?)%D') if start_fixed then start = start_fixed else errors = p.errorclass('Function nav_hyphen can\'t recognize the number "'..(start or '')..'" '..								 'in the first part of the "season" that was passed to it. '..								  'For e.g. "2015–16", "2015" is expected via "|2015|–|16|".') return p.failedcat(errors, 'H') end end local nstart = tonumber(start) --en dash check if hyph ~= '–' then trackcat(4, 'Navseasoncats range not using en dash') --nav still processable, but track end --sterilize finish & check for weird parents local tgaps  = {} --table of gap sizes found b/w terms    { [ ]    = 1 } local ttlens = {} --table of term lengths found w/i terms { [ ] = 1 } local tirregs = {} --table of ir/regular-term-length cats' "from"s & "to"s found local regularparent = true if (finish == -1) or --"Members of the Scottish Parliament 2021–present" (finish == 0)	 --"Members of the Scottish Parliament 2021–" then regularparent = false if maxseas == nil or maxseas == '' then maxseas = start --hide subsequent ranges end if finish == -1 then trackcat(14, 'Navseasoncats range ends (present)') else				 trackcat(15, 'Navseasoncats range ends (blank, MOS)') end elseif (start == finish) and (ttrackingcats[16] ~= '') --nav_year found isolated; check for surrounding hyphenated terms (e.g. UK MPs 1974) then trackcat(16, '') --reset for another check later trackcat(13, 'Navseasoncats range irregular, 0-length') ttlens[0] = 1 --calc ttlens for std cases below regularparent = 'isolated' end if (string.match(finish or '', '^%d+$') == nil) and (string.match(finish or '', '^%-%d+$') == nil) then local finish_fixed = mw.ustring.match(finish or '', '^%s*(%d%d?%d?%d?)%D') if finish_fixed then finish = finish_fixed else errors = p.errorclass('Function nav_hyphen can\'t recognize "'..(finish or '')..'" '..								 'in the second part of the "season" that was passed to it. '..								  'For e.g. "2015–16", "16" is expected via "|2015|–|16|".') return p.failedcat(errors, 'I') end else if string.len(finish) >= 5 then errors = p.errorclass('The second part of the season passed to function nav_hyphen should only be four or fewer digits, not "'..(finish or '')..'". '..								 'See MOS:DATERANGE for details.') return p.failedcat(errors, 'J') end end local nfinish = tonumber(finish) --save sterilized parent range for easier lookup later tirregs['from0'] = nstart tirregs['to0']  = nfinish --sterilize min/max local nminseas_default = -9999 local nmaxseas_default = 9999 local nminseas = tonumber(minseas) or nminseas_default --same behavior as nav_year local nmaxseas = tonumber(maxseas) or nmaxseas_default --same behavior as nav_year if nminseas > nstart then nminseas = nstart end if nmaxseas < nstart then nmaxseas = nstart end local lspace = ' ' --assume a leading space (most common) local tspace = ' ' --assume a trailing space (most common) if string.match(firstpart, '%($') then lspace =  end --DNE for "Madrid city councillors (2007–2011)"-type cats	if string.match(lastpart, '^%)') then tspace =  end --DNE for "Madrid city councillors (2007–2011)"-type cats --calculate term length/intRAseason size & finishing year local term_limit = 10 local t = 1 while t <= term_limit and regularparent == true do		local nish = nstart + t --use switchADBC to flip this sign to work for years BC, if/when the time comes if (nish == nfinish) or (string.match(nish, '%d?%d$') == finish) then ttlens[t] = 1 break end if t == term_limit then errors = p.errorclass('Function nav_hyphen can\'t determine a reasonable term length for "'..start..hyph..finish..'".') return p.failedcat(errors, 'K') end t = t + 1 end --apply MOS:DATERANGE to parent local lenstart = string.len(start) local lenfinish = string.len(finish) if lenstart == 4 and regularparent == true then --"2001–..." if t == 1 then --"2001–02" & "2001–2002" both allowed if lenfinish ~= 2 and lenfinish ~= 4 then errors = p.errorclass('The second part of the season passed to function nav_hyphen should be two or four digits, not "'..finish..'".') return p.failedcat(errors, 'L') end else --"2001–2005" is required for t > 1; track "2001–05"; anything else = error if lenfinish == 2 then trackcat(5, 'Navseasoncats range abbreviated (MOS)') elseif lenfinish ~= 4 then errors = p.errorclass('The second part of the season passed to function nav_hyphen should be four digits, not "'..finish..'".') return p.failedcat(errors, 'M') end end if finish == '00' then --full year required regardless of term length trackcat(5, 'Navseasoncats range abbreviated (MOS)') end end --calculate intERseason gap size local hgap_default    = 0 --assume & start at the most common case: 2001–02 -> 2002–03, etc.	local hgap_limit_reg   = 6 --less expensive per-increment (inc x 4) local hgap_limit_irreg = 6 --more expensive per-increment (inc x 23: inc x (k_bwd + k_fwd) = inc x (12 + 11)) local hgap_success = false local hgap = hgap_default while hgap <= hgap_limit_reg and regularparent == true do --verify local prevseason2 = firstpart..lspace..(nstart-t-hgap)..hyph..string.match(nstart-hgap, '%d?%d$')   ..tspace..lastpart local nextseason2 = firstpart..lspace..(nstart+t+hgap)..hyph..string.match(nstart+2*t+hgap, '%d?%d$')..tspace..lastpart local prevseason4 = firstpart..lspace..(nstart-t-hgap)..hyph..(nstart-hgap)   ..tspace..lastpart local nextseason4 = firstpart..lspace..(nstart+t+hgap)..hyph..(nstart+2*t+hgap)..tspace..lastpart if t == 1 then --test abbreviated range first, then full range, to be frugal with expensive functions if catexists(prevseason2) or --use 'or', in case we're at the edge of the cat structure, catexists(nextseason2) or --or we hit a "–00"/"–2000" situation on one side catexists(prevseason4) or			  catexists(nextseason4) then hgap_success = true break end elseif t > 1 then --test full range first, then abbreviated range, to be frugal with expensive functions if catexists(prevseason4) or --use 'or', in case we're at the edge of the cat structure, catexists(nextseason4) or --or we hit a "–00"/"–2000" situation on one side catexists(prevseason2) or			  catexists(nextseason2) then hgap_success = true break end end hgap = hgap + 1 end if hgap_success == false then hgap = tonumber(testgap) or hgap_default --tracked via defaultgapcat end --preliminary scan to determine ir/regular spacing of nearby cats; --to limit expensive function calls, MOS:DATERANGE-violating cats are ignored; --an irregular-term-length series should follow "YYYY..hyph..YYYY" throughout if hgap <= hgap_limit_reg then --also to isolate temp vars --find # of nav-visible ir/regular-term-length cats local bwanchor = nstart      --backward anchor/common year local fwanchor = bwanchor + t --forward anchor/common year if regularparent == 'isolated' then fwanchor = bwanchor end local spangreen = '[ j, g, k = ' --used for/when debugging via list-all-links=yes local spanblue = ' ' local spanred = ' ( '		local span = ' '		local lastg = nil --to check for run-on searches		local lastk = nil --to check for run-on searches		local endfound = false --switch used to stop searching forward		local iirregs = 0 --index of tirregs[] for j < 0, since search starts from parent		local j = -3 --index of tirregs[] for j > 0 & pseudo nav position		while j <= 3 do			if j < 0 then --search backward from parent				local gbreak = false --switch used to break out of g-loop				local g = 0 --gap size				while g <= hgap_limit_irreg do					local k = 0 --term length: 0 = "0-length", 1+ = normal					while k <= term_limit do						local from = bwanchor - k - g						local to  = bwanchor - g						local full = mw.text.trim( firstpart..lspace..from..hyph..to..tspace..lastpart )						if k == 0 then							if regularparent ~= 'isolated' then --+restrict to g == 0 if repeating year problems arise								to = '0-length' full = mw.text.trim( firstpart..lspace..from..tspace..lastpart ) if catlinkfollowr( frame, full ).rtarget ~= nil then --#R followed table.insert( tlistallbwd, spangreen..j..', '..g..', '..k..span..'] '..full..spanred..'#R ignored'..span..')' )									full, to = ,  --don't use/follow 0-length cat #Rs from nav_hyphen; otherwise gets messy								end							end						end						if (k >= 1) or		 --the normal case; only continue k = 0 if 0-length found						   (to == '0-length') --ghetto "continue" (thx Lua) to avoid expensive searches for "UK MPs 1974-1974", etc.						then							table.insert( tlistallbwd, spangreen..j..', '..g..', '..k..span..'] '..full )							if (k == 1) and							   (g == 0 or g == 1) and							   (catexists(full) == false)							then --allow bare-bones MOS:DATERANGE alternation, in case we're on a 0|1-gap, 1-year term series								local to2 = string.match(to, '%d%d$')								if to2 and to2 ~= '00' then --and not at a century transition (i.e. 1999–2000)									to = to2									full = mw.text.trim( firstpart..lspace..from..hyph..to..tspace..lastpart ) table.insert( tlistallbwd, spangreen..j..', '..g..', '..k..span..'] '..full ) end end if catexists(full) then if to == '0-length' then trackcat(13, 'Navseasoncats range irregular, 0-length') end tlistallbwd[#tlistallbwd] = spanblue..tlistallbwd[#tlistallbwd]..span..' (found)' ttlens[ find_duration(full) ] = 1 tgaps[g] = 1 iirregs = iirregs + 1 tirregs['from-'..iirregs] = from tirregs['to-'..iirregs] = to								bwanchor = from --ratchet down if to ~= '0-length' then gbreak = true break else g = 0 --soft-reset g, to keep stepping thru k									j = j + 1 --save, but keep searching thru k									if j > 3 then --lest we keep searching & finding 0-length cats ("MEPs for the Republic of Ireland 1973" & down) gbreak = true break end end end end --ghetto "continue" k = k + 1 lastk = k					end --while k					if gbreak == true then break end g = g + 1 lastg = g				end --while g			end --if j < 0 if j > 0 and endfound == false then --search forward from parent local gbreak = false --switch used to break out of g-loop local g = 0 --gap size while g <= hgap_limit_irreg do					local k = -2 --term length: -2 = "0-length", -1 = "2020–present", 0 = "2020–", 1+ = normal while k <= term_limit do						local from = fwanchor + g						local to4 = fwanchor + k + g	--override carefully local to2 = nil				--last 2 digits of to4, IIF exists if k == -1 then to4 = 'present'	--see if end-cat exists (present) elseif k == 0 then to4 = '' end	--see if end-cat exists (blank) local full = mw.text.trim( firstpart..lspace..from..hyph..to4..tspace..lastpart ) if k == -2 then if regularparent ~= 'isolated' then --+restrict to g == 0 if repeating year problems arise to4 = '0-length' --see if 0-length cat exists full = mw.text.trim( firstpart..lspace..from..tspace..lastpart ) if catlinkfollowr( frame, full ).rtarget ~= nil then --#R followed table.insert( tlistallfwd, spangreen..j..', '..g..', '..k..span..'] '..full..spanred..'#R ignored'..span..')' )									full, to4 = ,  --don't use/follow 0-length cat #Rs from nav_hyphen; otherwise gets messy								end							end						end						if (k >= -1) or		  --only continue k = -2 if 0-length found						   (to4 == '0-length') --ghetto "continue" (thx Lua) to avoid expensive searches for "UK MPs 1974-1974", etc.						then							table.insert( tlistallfwd, spangreen..j..', '..g..', '..k..span..'] '..full )							if (k == 1) and							   (g == 0 or g == 1) and							   (catexists(full) == false)							then --allow bare-bones MOS:DATERANGE alternation, in case we're on a 0|1-gap, 1-year term series								to2 = string.match(to4, '%d%d$')								if to2 and to2 ~= '00' then --and not at a century transition (i.e. 1999–2000)									full = mw.text.trim( firstpart..lspace..from..hyph..to2..tspace..lastpart ) table.insert( tlistallfwd, spangreen..j..', '..g..', '..k..span..'] '..full ) end end if catexists(full) then if to4 == '0-length' then if rtarget(frame, full) == full then --only use 0-length cats that don't #R trackcat(13, 'Navseasoncats range irregular, 0-length') end end tirregs['from'..j] = from tirregs['to'..j] = (to2 or to4) if (k == -1) or (k == 0) then endfound = true --tentative else --k == { -2, > 0 } tlistallfwd[#tlistallfwd] = spanblue..tlistallfwd[#tlistallfwd]..span..' (found)' ttlens[ find_duration(full) ] = 1 tgaps[g] = 1 endfound = false if to4 ~= '0-length' then --k > 0 fwanchor = to4 --ratchet up										gbreak = true break --only break on k > 0 b/c old end-cat #Rs still exist like "Members of the Scottish Parliament 2011–" else --k == -2 j = j + 1 --save, but keep searching k's, in case "1974" → "1974-1979" if j > 3 then --lest we keep searching & finding 0-length cats ("2018 CONCACAF Champions League" & up) gbreak = true break end end end end end --ghetto "continue" k = k + 1 lastk = k					end --while k					if gbreak == true then break end g = g + 1 lastg = g				end --while g			end --if j > 0 if (lastg == (hgap_limit_irreg + 1)) and (lastk == (term_limit + 1)) then --search exhausted if j < 0 then j = 0 --bwd search exhausted; continue fwd elseif j > 0 then break end --fwd search exhausted end j = j + 1 end --while j <= 3 end --if hgap <= hgap_limit_reg --begin navhyphen local navh = '{| class="toccolours hlist" style="text-align: center; margin: auto;"\n'..'|\n' local terminalcat = false --switch used to hide future cats local terminaltxt = nil local i = -3 --nav position while i <= 3 do		local from = nstart + i*(t+hgap) --the logical, but not necessarily correct, 'from' if tirregs['from'..i] then from = tonumber(tirregs['from'..i]) end --prefer irregular term table local from2 = string.match(from, '%d?%d$') local to = tostring(from+t)	--the logical, naive range, but if tirregs['to'..i] then	--prefer irregular term table to = tirregs['to'..i]		elseif regularparent == false and tirregs and i > 0 then to = tirregs['to-1']	--special treatment for parent terminal cats, since they have no natural 'to' end local to2 = string.match(to, '%d?%d$') local tofinal = (to2 or '')   --assume t=1 and abbreviated 'to' (the most common case) if t > 1 or                   --per MOS:DATERANGE (e.g. 1999-2004) (from2 - (to2 or from2)) > 0 --century transition exception (e.g. 1999–2000) then tofinal = (to or '')      --default to the MOS-correct format, in case no fallbacks found end if to == '0-length' then tofinal = to		end --check existance of 4-digit, MOS-correct range, with abbreviation fallback if tofinal ~= '0-length' then if t > 1 and string.len(from) == 4 then --e.g. 1999-2004 --determine which link exists (full or abbr) local full = firstpart..lspace..from..hyph..tofinal..tspace..lastpart if not catexists(full) then local abbr = firstpart..lspace..from..hyph..to2..tspace..lastpart if catexists(abbr) then tofinal = (to2 or '') --rv to MOS-incorrect format; if full AND abbr DNE, then tofinal is still in its MOS-correct format end end elseif t == 1 then --full-year consecutive ranges are also allowed local abbr = firstpart..lspace..from..hyph..tofinal..tspace..lastpart --assume tofinal is in abbr format if not catexists(abbr) and tofinal ~= to then local full = firstpart..lspace..from..hyph..to..tspace..lastpart if catexists(full) then tofinal = (to or '') --if abbr AND full DNE, then tofinal is still in its abbr format (unless it's a century transition) end	end	end	end --populate navh if i ~= 0 then --left/right navh local orig = firstpart..lspace..from..hyph..tofinal..tspace..lastpart local disp = from..hyph..tofinal if tofinal == '0-length' then orig = firstpart..lspace..from..tspace..lastpart disp = from end local catlink = catlinkfollowr(frame, orig, disp, true) --force terminal cat display if terminalcat == false then terminaltxt = find_terminaltxt( disp ) --also sets tracking cats terminalcat = (terminaltxt ~= nil) end if catlink.rtarget and avoidself then --a {{Category redirect}} was followed, figure out why --determine new term length & gap size ttlens[ find_duration( catlink.rtarget ) ] = 1 if i > -3 then local lastto = tirregs['to'..(i-1)] if lastto == nil then local lastfrom = nstart + (i-1)*(t+hgap) lastto = lastfrom+t --use last logical 'from' to calc lastto end if lastto then local gapcat = lastto..'-'..from --dummy cat to calc with local gap = find_duration(gapcat) or -1	--in case of nil, tgaps[ gap ] = 1						--tgaps[-1] is ignored end end --display/tracking handling local base_regex = '%d+[–-]%d+' local origbase = mw.ustring.gsub(orig, base_regex, '') local rtarbase, rtarbase_success = mw.ustring.gsub(catlink.rtarget, base_regex, '') if rtarbase_success == 0 then local base_regex_lax = '%d%d%d%d' --in case rtarget is a year cat rtarbase, rtarbase_success = mw.ustring.gsub(catlink.rtarget, base_regex_lax, '') end local terminal_regex = '%d+[–-]'..(terminaltxt or '')..'$' --more manual ORs bc Lua regex sux if mw.ustring.match(orig, terminal_regex) then origbase = mw.ustring.gsub(orig, terminal_regex, '') end if mw.ustring.match(catlink.rtarget, terminal_regex) then --finagle/overload terminalcat type to set nmaxseas on 1st occurence only if terminalcat == false then terminalcat = 1 end local dummy = find_terminaltxt( catlink.rtarget ) --also sets tracking cats rtarbase = mw.ustring.gsub(catlink.rtarget, terminal_regex, '') end origbase = mw.text.trim(origbase) rtarbase = mw.text.trim(rtarbase) if origbase ~= rtarbase then trackcat(6, 'Navseasoncats range redirected (base change)') elseif terminalcat == 1 then trackcat(8, 'Navseasoncats range redirected (end)') else --origbase == rtarbase local all4s_regex = '%d%d%d%d[–-]%d%d%d%d' local orig_all4s = mw.ustring.match(orig, all4s_regex) local rtar_all4s = mw.ustring.match(catlink.rtarget, all4s_regex) if orig_all4s and rtar_all4s then trackcat(10, 'Navseasoncats range redirected (other)') else local year_regex1 = '%d%d%d%d$' local year_regex2 = '%d%d%d%d[%s%)]'						local year_rtar = mw.ustring.match(catlink.rtarget, year_regex1) or										 mw.ustring.match(catlink.rtarget, year_regex2)						if orig_all4s and year_rtar then							trackcat(7, 'Navseasoncats range redirected (var change)')						else							trackcat(9, 'Navseasoncats range redirected (MOS)')						end					end				end			end			if terminalcat then --true or 1				if type(terminalcat) ~= 'boolean' then nmaxseas = from end --only want to do this once				terminalcat = true --done finagling/overloading			end			if (from >= 0) and (nminseas <= from) and (from <= nmaxseas) then				navh = navh..'*'..catlink.navelement..'\n'				if terminalcat then nmaxseas = nminseas_default end --prevent display of future ranges			else				local hidden = ' '..disp..' '				navh = navh..'*'..hidden..'\n'				if listall then					tlistall[#tlistall] = tlistall[#tlistall]..' ('..hidden..')' end end else --center navh if finish == -1 then finish = 'present' elseif finish == 0 then finish = ' '..start..' ' end local disp = start..hyph..finish if regularparent == 'isolated' then disp = start end navh = navh..'*'..disp..'\n' end i = i + 1 end --tracking cats & finalize if avoidself then local igaps = 0 --# of diff gap sizes > 0 found local itlens = 0 --# of diff term lengths found for s = 1, hgap_limit_reg do --must loop; #tgaps, #ttlens unreliable igaps = igaps + (tgaps[s] or 0) end for s = 0, term_limit do			itlens = itlens + (ttlens[s] or 0) end if igaps > 0 then trackcat(11, 'Navseasoncats range gaps') end if itlens > 1 and ttrackingcats[13] == '' then --avoid duplication in "Navseasoncats range irregular, 0-length" trackcat(12, 'Navseasoncats range irregular') end end isolatedcat defaultgapcat(not hgap_success) if listall then return listalllinks else return navh..'|}' end end

--=========================={{ nav_tvseason  }}============================

local function nav_tvseason( frame, firstpart, tv, lastpart, maximumtv ) --Expects a PAGENAME of the form "Futurama (season 1) episodes", where --	firstpart = Futurama (season	--	tv       = 1	--	lastpart  = ) episodes --	maximumtv = 7 ('max' tv season parameter; optional; defaults to 9999) tv = tonumber(tv) if tv == nil then errors = p.errorclass('Function nav_tvseason can\'t recognize the TV season number sent to its 2nd parameter.') return p.failedcat(errors, 'T') end local maxtv = tonumber(maximumtv) or 9999 --allow +/- qualifier if maxtv < tv then maxtv = tv end --input error; maxtv should be >= parent --begin navtvseason local navt = '{| class="toccolours hlist" style="text-align: center; margin: auto;"\n'..'|\n' local i = -5 --nav position while i <= 5 do		local t = tv + i		if i ~= 0 then --left/right navt local catlink = catlinkfollowr( frame, firstpart..' '..t..lastpart, t ) if (t >= 1 and t <= maxtv) then --hardcode mintv if catlink.rtarget then --a {{Category redirect}} was followed trackcat(25, 'Navseasoncats TV season redirected') end navt = navt..'*'..catlink.navelement..'\n' else local hidden = ' '..'0'..' ' --'0' to maintain dot spacing navt = navt..'*'..hidden..'\n' if listall then tlistall[#tlistall] = tlistall[#tlistall]..' ('..hidden..')' end end else --center navt navt = navt..'*'..tv..'\n' end i = i + 1 end isolatedcat if listall then return listalllinks else return navt..'|}' end end

--==========================={{ nav_decade  }}=============================

local function nav_decade( frame, firstpart, decade, lastpart, mindecade, maxdecade ) --Expects a PAGENAME of the form "Some sequential 2000 example cat", where --	firstpart = Some sequential --	decade   = 2000 --	lastpart = example cat --	mindecade = 1800 ('min' decade parameter; optional; defaults to -9999) --	maxdecade = 2020 ('max' decade parameter; optional; defaults to 9999) --sterilize dec local dec = sterilizedec(decade) if dec == nil then errors = p.errorclass('Function nav_decade was sent "'..(decade or '')..'" as its 2nd parameter, '..							'but expects a 1 to 4-digit year ending in "0".') return p.failedcat(errors, 'D') end local ndec = tonumber(dec) --sterilize mindecade & determine AD/BC local mindefault = '-9999' local mindec = sterilizedec(mindecade) --returns a tostring(unsigned int), or nil if mindec then if string.match(mindecade, '-%d') or		  string.match(mindecade, 'BC') then mindec = '-'..mindec --better +/-0 behavior with strings (0-initialized int == "-0" string...) end elseif mindec == nil and mindecade and mindecade ~= '' then errors = p.errorclass('Function nav_decade was sent "'..(mindecade or '')..'" as its 4th parameter, '..							'but expects a 1 to 4-digit year ending in "0", the earliest decade to be shown.') return p.failedcat(errors, 'E') else --mindec == nil mindec = mindefault --tonumber later, after error checks end --sterilize maxdecade & determine AD/BC local maxdefault = '9999' local maxdec = sterilizedec(maxdecade) --returns a tostring(unsigned int), or nil + error if maxdec then if string.match(maxdecade, '-%d') or		  string.match(maxdecade, 'BC') then                    --better +/-0 behavior with strings (0-initialized int == "-0" string...), maxdec = '-'..maxdec --but a "-0" string -> tonumber -> tostring = "-0", end                     --and a  "0" string -> tonumber -> tostring =  "0" elseif maxdec == nil and maxdecade and maxdecade ~= '' then errors = p.errorclass('Function nav_decade was sent "'..(maxdecade or '')..'" as its 5th parameter, '..							'but expects a 1 to 4-digit year ending in "0", the highest decade to be shown.') return p.failedcat(errors, 'F') else --maxdec == nil maxdec = maxdefault end local tspace = ' ' --assume trailing space for "1950s in X"-type cats if string.match(lastpart, '^-') then tspace = '' end --DNE for "1970s-related"-type cats --AD/BC switches & vars local parentBC = string.match(lastpart, '^BC') --following the "0s BC" convention for all years BC	lastpart = mw.ustring.gsub(lastpart, '^BC%s*', '') --handle BC separately; AD never used --TODO?: handle BCE, but only if it exists in the wild local dec0to40AD = (ndec >= 0 and ndec <= 40 and not parentBC) --special behavior in this range local switchADBC = 1                --  1=AD parent if parentBC then switchADBC = -1 end -- -1=BC parent; possibly adjusted later local BCdisp = '' local D = -math.huge --secondary switch & iterator for AD/BC transition --check non-default min/max more carefully if mindec ~= mindefault then if tonumber(mindec) > ndec*switchADBC then mindec = tostring(ndec*switchADBC) --input error; mindec should be <= parent end end if maxdec ~= maxdefault then if tonumber(maxdec) < ndec*switchADBC then maxdec = tostring(ndec*switchADBC) --input error; maxdec should be >= parent end end local nmindec = tonumber(mindec) --similar behavior to nav_year & nav_nordinal local nmaxdec = tonumber(maxdec) --similar behavior to nav_nordinal --begin navdecade local bnb = '' --border/no border if navborder == false then --for Navseasoncats year and decade bnb = ' border-style: none; background-color: transparent;' end local navd = '{| class="toccolours hlist" style="text-align: center; margin: auto;'..bnb..'"\n'..'|\n' local i = -50 --nav position x 10 while i <= 50 do		local d = ndec + i*switchADBC local BC = '' BCdisp = '' if dec0to40AD then if D < -10 then d = math.abs(d + 10) --b/c 2 "0s" decades exist: "0s BC" & "0s" (AD) BC = 'BC ' if d == 0 then D = -10 --track 1st d = 0 use (BC) end elseif D >= -10 then D = D + 10 --now iterate from 0s AD				d = D     --2nd d = 0 use end elseif parentBC then if switchADBC == -1 then --parentBC looking at the BC side (the common case) BC = 'BC ' if d == 0 then    --prepare to switch to the AD side on the next iteration switchADBC = 1 --1st d = 0 use (BC) D = -10       --prep end elseif switchADBC == 1 then --switched to the AD side D = D + 10 --now iterate from 0s AD				d = D     --2nd d = 0 use (on first use) end end if BC ~= '' and ndec <= 50 then BCdisp = ' BC' --show BC for all BC decades whenever a "0s" is displayed on the nav end --determine target cat local disp = d..'s'..BCdisp local catlink = catlinkfollowr( frame, firstpart..' '..d..'s'..tspace..BC..lastpart, disp ) if catlink.rtarget then --a {{Category redirect}} was followed trackcat(18, 'Navseasoncats decade redirected') end --populate left/right navd local shown = navcenter(i, catlink) local hidden = ' '..disp..' ' local dsign = d --use d for display & dsign for logic if BC ~= '' then dsign = -dsign end if (nmindec <= dsign) and (dsign <= nmaxdec) then if dsign == 0 and (nmindec == 0 or nmaxdec == 0) then --distinguish b/w -0 (BC) & 0 (AD) --"zoom in" on +/- 0 and turn dsign/min/max temporarily into +/- 1 for easier processing local zsign, zmin, zmax = 1, nmindec, nmaxdec if BC ~= '' then zsign = -1 end if    mindec == '-0' then zmin = -1 elseif mindec == '0' then zmin =  1 end if    maxdec == '-0' then zmax = -1 elseif maxdec == '0' then zmax =  1 end if (zmin <= zsign) and (zsign <= zmax) then navd = navd..shown hidden = nil else navd = navd..'*'..hidden..'\n' end else navd = navd..shown --the common case hidden = nil end else navd = navd..'*'..hidden..'\n' end if listall and hidden then tlistall[#tlistall] = tlistall[#tlistall]..' ('..hidden..')' end i = i + 10 end isolatedcat if listall then return listalllinks else return navd..'|}' end end

--============================{{ nav_year  }}==============================

local function nav_year( frame, firstpart, year, lastpart, minimumyear, maximumyear ) --Expects a PAGENAME of the form "Some sequential 1760 example cat", where --	firstpart  = Some sequential --	year       = 1760 --	lastpart   = example cat --	minimumyear = 1758 ('min' year parameter; optional) --	maximumyear = 1800 ('max' year parameter; optional) local minyear_default = -9999 local maxyear_default = 9999 year = tonumber(year) or tonumber(mw.ustring.match(year or '', '^%s*(%d*)')) local minyear = tonumber(string.match(minimumyear or '', '-?%d+')) or minyear_default --allow +/- qualifier local maxyear = tonumber(string.match(maximumyear or '', '-?%d+')) or maxyear_default --allow +/- qualifier if string.match(minimumyear or '', 'BC') then minyear = -math.abs(minyear) end --allow BC qualifier (AD otherwise assumed) if string.match(maximumyear or '', 'BC') then maxyear = -math.abs(maxyear) end --allow BC qualifier (AD otherwise assumed) if year == nil then errors = p.errorclass('Function nav_year can\'t recognize the year sent to its 2nd parameter.') return p.failedcat(errors, 'Y') end --AD/BC switches & vars local yearBCElastparts = { --needed for parent = AD 1-5, when the BC/E format is unknown --"BCE" removed to match both AD & BCE cats; easier & faster than multiple string.matchs ['example_Hebrew people_example'] = 'BCE', --example entry format; add to & adjust as needed }	local parentAD = string.match(firstpart, 'AD$') --following the "AD 1" convention from AD 1 to AD 10 local parentBC = string.match(lastpart, '^BCE?') --following the "1 BC" convention for all years BC	firstpart = mw.ustring.gsub(firstpart, '%s*AD$', '') --handle AD/BC separately for easier & faster accounting lastpart = mw.ustring.gsub(lastpart,  '^BCE?%s*', '') local BCe = parentBC or yearBCElastparts[lastpart] or 'BC' --"BC" default local year1to10 = (year >= 1 and year <= 10) local year1to10ADBC = year1to10 and (parentBC or parentAD) --special behavior 1-10 for low-# non-year series local year1to15AD = (year >= 1 and year <= 15 and not parentBC) --special behavior 1-15 for AD/BC display local switchADBC = 1                --  1=AD parent if parentBC then switchADBC = -1 end -- -1=BC parent; possibly adjusted later local Y = 0 --secondary iterator for AD-on-a-BC-parent if minyear > year*switchADBC then minyear = year*switchADBC end --input error; minyear should be <= parent if maxyear < year*switchADBC then maxyear = year*switchADBC end --input error; maxyear should be >= parent local lspace = ' ' --leading space before year, after firstpart if string.match(firstpart, '[%-VW]$') then lspace = '' --e.g. "Straight-8 engines" end local tspace = ' ' --trailing space after year, before lastpart if string.match(lastpart, '^-') then tspace = '' --e.g. "2018-related timelines" end --determine interyear gap size to condense special category types, if possible local ygapdefault = 1 --assume/start at the most common case: 2001, 2002, etc.	local ygap = ygapdefault if string.match(lastpart, 'presidential') then local ygap1, ygap2 = ygapdefault, ygapdefault --need to determine previous & next year gaps indepedently local ygap1_success, ygap2_success = false, false local prevseason = nil while ygap1 <= 5 do --Czech Republic, Poland, Sri Lanka, etc. have 5-year terms prevseason = firstpart..lspace..(year-ygap1)..tspace..lastpart if catexists(prevseason) then ygap1_success = true break end ygap1 = ygap1 + 1 end local nextseason = nil while ygap2 <= 5 do --Czech Republic, Poland, Sri Lanka, etc. have 5-year terms nextseason = firstpart..lspace..(year+ygap2)..tspace..lastpart if catexists(nextseason) then ygap2_success = true break end ygap2 = ygap2 + 1 end if ygap1_success and ygap2_success then if ygap1 == ygap2 then ygap = ygap1 end elseif ygap1_success then ygap = ygap1 elseif ygap2_success then ygap = ygap2 end end --skip non-existing years, if requested local ynogaps = {} --populate with existing years in the range, at most, [year - (skipgaps_limit * 5), year + (skipgaps_limit * 5)] local skipgaps_limit = 25 if skipgaps then if minyear == minyear_default then minyear = 0 --automatically set minyear to 0, as AD/BC not supported anyway end if (year > 70) or --add support for AD/BC (<= AD 10) if/when needed (minyear >= 0 and --must be a non-year series like "AC with 0 elements"		  	not parentAD and not parentBC) then local yskipped = {} --track skipped y's to avoid double-checking local cat, found, Yeary --populate nav element queue outwards positively from the parent local Year = year --to save/ratchet progression local i = 1 while i <= 5 do				local y = 1 while y <= skipgaps_limit do					found = false Yeary = Year + y					if yskipped[Yeary] == nil then yskipped[Yeary] = Yeary cat = firstpart..lspace..Yeary..tspace..lastpart found = catexists(cat) if found then break end end y = y + 1 end if found then Year = Yeary else         Year = Year + 1 end ynogaps[i] = Year i = i + 1 end ynogaps[0] = year --the parent --populate nav element queue outwards negatively from the parent Year = year --reset ratchet i = -1 while i >= -5 do				local y = -1 while y >= -skipgaps_limit do					found = false Yeary = Year + y					if yskipped[Yeary] == nil then yskipped[Yeary] = Yeary cat = firstpart..lspace..Yeary..tspace..lastpart found = catexists(cat) if found then break end end y = y - 1 end if found then Year = Yeary else         Year = Year - 1 end ynogaps[i] = Year i = i - 1 end else skipgaps = false --AD/BC not supported end end --begin navyears local navy = '{| class="toccolours hlist" style="text-align: center; margin: auto;"\n'..'|\n' local y	local j = 0 --decrementor for special cases "2021 World Rugby Sevens Series" -> "2021–2022" local i = -5 --nav position while i <= 5 do		if skipgaps then y = ynogaps[i] else y = year + i*ygap*switchADBC - j		end local BCdisp = '' if i ~= 0 then --left/right navy local AD = '' local BC = '' if year1to15AD and not (year1to10 and not year1to10ADBC) --don't AD/BC 1-10's if parents don't contain AD/BC then if year >= 11 then --parent = AD 11-15 if y <= 10 then --prepend AD on y = 1-10 cats only, per existing cats AD = 'AD ' end elseif year >= 1 then --parent = AD 1-10 if y <= 0 then BC = BCe..' ' y = math.abs(y - 1) --skip y = 0 (DNE) elseif y >= 1 and y <= 10 then --prepend AD on y = 1-10 cats only, per existing cats AD = 'AD ' end end elseif parentBC then if switchADBC == -1 then --displayed y is in the BC regime if y >= 1 then    --the common case BC = BCe..' ' elseif y == 0 then --switch from BC to AD regime switchADBC = 1 end end if switchADBC == 1 then --displayed y is now in the AD regime Y = Y + 1 --skip y = 0 (DNE) y = Y    --easiest solution: start another iterator for these AD y's displayed on a BC year parent AD = 'AD ' end end if BC ~= '' and year <= 5 then --only show 'BC' for parent years <= 5: saves room, easier to read, BCdisp = ' '..BCe         --and 6 is the first/last nav year that doesn't need a disambiguator; end                           --the center/parent year will always show BC, so no need to show it another 10x --populate left/right navy local ysign = y --use y for display & ysign for logic local disp = y..BCdisp if BC ~= '' then ysign = -ysign end local firsttry = firstpart..lspace..AD..y..tspace..BC..lastpart if (minyear <= ysign) and (ysign <= maxyear) then local catlinkAD = catlinkfollowr( frame, firsttry, disp ) --try AD				local catlink = catlinkAD --tentative winner if AD ~= '' then --for "ACArt with 5 suppressed elements"-type cats local catlinkNoAD = catlinkfollowr( frame, firstpart..lspace..y..tspace..BC..lastpart, disp ) --try !AD if catlinkNoAD.catexists == true then catlink = catlinkNoAD --usurp elseif listall then tlistall[#tlistall] = tlistall[#tlistall]..' (tried; not displayed){{sup|1}}' end end if (AD..BC == '') and (catlink.catexists == false) and (y >= 1000) then --!ADBC & DNE; 4-digit only, to be frugal --try basic hyphenated cats: 1-year, endash, MOS-correct only, no #Rs local yHyph_4 = y..'–'..(y+1) --try 2010–2011 type cats local catlinkHyph_4 = catlinkfollowr( frame, firstpart..lspace..yHyph_4..tspace..BC..lastpart, yHyph_4 ) if catlinkHyph_4.catexists and catlinkHyph_4.rtarget == nil then --exists & no #Rs catlink = catlinkHyph_4 --usurp trackcat(27, 'Navseasoncats year and range') else if listall then tlistall[#tlistall] = tlistall[#tlistall]..' (tried; not displayed){{sup|2}}' end local yHyph_2 = y..'–'..string.match(y+1, '%d%d$') --try 2010–11 type cats if i == 1 then local yHyph_2_special = (y-1)..'–'..string.match(y, '%d%d$') --try special case 2021 -> 2021–22 local catlinkHyph_2_special = catlinkfollowr( frame, firstpart..lspace..yHyph_2_special..tspace..BC..lastpart, yHyph_2_special ) if catlinkHyph_2_special.catexists and catlinkHyph_2_special.rtarget == nil then --exists & no #Rs catlink = catlinkHyph_2_special --usurp trackcat(27, 'Navseasoncats year and range') j = 1 elseif listall then tlistall[#tlistall] = tlistall[#tlistall]..' (tried; not displayed){{sup|3}}' end end if not (i == 1 and j == 1) then local catlinkHyph_2 = catlinkfollowr( frame, firstpart..lspace..yHyph_2..tspace..BC..lastpart, yHyph_2 ) if catlinkHyph_2.catexists and catlinkHyph_2.rtarget == nil then --exists & no #Rs catlink = catlinkHyph_2 --usurp trackcat(27, 'Navseasoncats year and range') elseif listall then tlistall[#tlistall] = tlistall[#tlistall]..' (tried; not displayed){{sup|4}}' end end end end if catlink.rtarget then --#R followed; determine why local r = catlink.rtarget local c = catlink.cat local year_regex = '%d%d%d%d[–-]?%d?%d?%d?%d?' --prioritize year/range stripping, e.g. for "2006 Super 14 season" local hyph_regex = '%d%d%d%d[–-]%d+' --stricter local num_regex  = '%d+' --strip any number otherwise local final_regex = nil  --best choice goes here if mw.ustring.match(r, year_regex) and mw.ustring.match(c, year_regex) then final_regex = year_regex elseif mw.ustring.match(r, num_regex) and mw.ustring.match(c, num_regex) then final_regex = num_regex end if final_regex then local r_base = mw.ustring.gsub(r, final_regex, '') local c_base = mw.ustring.gsub(c, final_regex, '') if r_base ~= c_base then trackcat(19, 'Navseasoncats year redirected (base change)') --acceptable #R target elseif mw.ustring.match(r, hyph_regex) then trackcat(20, 'Navseasoncats year redirected (var change)') --e.g. "2008 in Scottish women's football" to "2008–09" else trackcat(21, 'Navseasoncats year redirected (other)') --exceptions go here end else trackcat(20, 'Navseasoncats year redirected (var change)') --e.g. "V2 engines" to "V-twin engines" end end navy = navy..'*'..catlink.navelement..'\n' else --OOB vs min/max local hidden = ' '..disp..' ' navy = navy..'*'..hidden..'\n' if listall then local dummy = catlinkfollowr( frame, firsttry, disp ) tlistall[#tlistall] = tlistall[#tlistall]..' ('..hidden..')' end end else --center navy if parentBC then BCdisp = ' '..BCe end navy = navy..'*'..year..BCdisp..'\n' end i = i + 1 end isolatedcat if listall then return listalllinks else return navy..'|}' end end

--==========================={{ nav_roman  }}==============================

local function nav_roman( frame, firstpart, roman, lastpart, minimumrom, maximumrom ) local toarabic = require('Module:ConvertNumeric').roman_to_numeral local toroman = require('Module:Roman').main --sterilize/convert rom/num local num = tonumber(toarabic(roman)) local rom = toroman({ [1] = num }) if num == nil or rom == nil then --out of range or some other error errors = p.errorclass('Function nav_roman can\'t recognize one or more of "'..(num or 'nil')..'" & "'..							(rom or 'nil')..'" in category "'..firstpart..' '..roman..' '..lastpart..'".') return p.failedcat(errors, 'R') end --sterilize min/max local minrom = tonumber(minimumrom or ) or tonumber(toarabic(minimumrom or )) local maxrom = tonumber(maximumrom or ) or tonumber(toarabic(maximumrom or )) if minrom < 1 then minrom = 1 end   --toarabic returns -1 on error if maxrom < 1 then maxrom = 9999 end --toarabic returns -1 on error if minrom > num then minrom = num end if maxrom < num then maxrom = num end --begin navroman local navr = '{| class="toccolours hlist" style="text-align: center; margin: auto;"\n'..'|\n' local i = -5 --nav position while i <= 5 do		local n = num + i		if n >= 1 then local r = toroman({ [1] = n }) if i ~= 0 then --left/right navr local catlink = catlinkfollowr( frame, firstpart..' '..r..' '..lastpart, r ) if minrom <= n and n <= maxrom then if catlink.rtarget then --a {{Category redirect}} was followed trackcat(22, 'Navseasoncats roman numeral redirected') end navr = navr..'*'..catlink.navelement..'\n' else local hidden = ' '..r..' ' navr = navr..'*'..hidden..'\n' if listall then tlistall[#tlistall] = tlistall[#tlistall]..' ('..hidden..')' end end else --center navr navr = navr..'*'..r..'\n' end else navr = navr..'* '..'I'..' \n' end i = i + 1 end isolatedcat if listall then return listalllinks else return navr..'|}' end end

--=========================={{ nav_nordinal  }}============================

local function nav_nordinal( frame, firstpart, ord, lastpart, minimumord, maximumord ) local nord = tonumber(ord) local minord = tonumber(string.match(minimumord or '', '(-?%d+)[snrt]?[tdh]?')) or -9999 --allow full ord & +/- qualifier local maxord = tonumber(string.match(maximumord or '', '(-?%d+)[snrt]?[tdh]?')) or 9999 --allow full ord & +/- qualifier if string.match(minimumord or '', 'BC') then minord = -math.abs(minord) end --allow BC qualifier (AD otherwise assumed) if string.match(maximumord or '', 'BC') then maxord = -math.abs(maxord) end --allow BC qualifier (AD otherwise assumed) local temporal = string.match(lastpart, 'century') or					 string.match(lastpart, 'millennium') local tspace = ' ' --assume a trailing space after ordinal if string.match(lastpart, '^-') then tspace = '' end --DNE for "19th-century"-type cats --AD/BC switches & vars local ordBCElastparts = { --needed for parent = AD 1-5, when the BC/E format is unknown --lists the lastpart of valid BCE cats --"BCE" removed to match both AD & BCE cats; easier & faster than multiple string.matchs ['-century Hebrew people'] = 'BCE', --WP:CFD/Log/2016 June 21#Category:11th-century BC Hebrew people ['-century Jews']         = 'BCE', --co-nominated ['-century Judaism']      = 'BCE', --co-nominated ['-century rabbis']       = 'BCE', --co-nominated ['-century High Priests of Israel'] = 'BCE', }	local parentBC = mw.ustring.match(lastpart, '%s(BCE?)')      --"1st-century BC" format local lastpartNoBC = mw.ustring.gsub(lastpart, '%sBCE?', '') --easier than splitting lastpart up in 2; AD never used local BCe = parentBC or ordBCElastparts[lastpartNoBC] or 'BC' --"BC" default local switchADBC = 1                --  1=AD parent if parentBC then switchADBC = -1 end -- -1=BC parent; possibly adjusted later local O = 0 --secondary iterator for AD-on-a-BC-parent if not temporal and minord < 1 then minord = 1 end --nothing before "1st parliament", etc.	if minord > nord*switchADBC then minord = nord*switchADBC end --input error; minord should be <= parent if maxord < nord*switchADBC then maxord = nord*switchADBC end --input error; maxord should be >= parent --begin navnordinal local bnb = '' --border/no border if navborder == false then --for Navseasoncats decade and century bnb = ' border-style: none; background-color: transparent;' end local navo = '{| class="toccolours hlist" style="text-align: center; margin: auto;'..bnb..'"\n'..'|\n' local i = -5 --nav position while i <= 5 do		local o = nord + i*switchADBC local BC = '' local BCdisp = '' if parentBC then if switchADBC == -1 then --parentBC looking at the BC side if o >= 1 then    --the common case BC = ' '..BCe elseif o == 0 then --switch to the AD side BC = '' switchADBC = 1 end end if switchADBC == 1 then --displayed o is now in the AD regime O = O + 1 --skip o = 0 (DNE) o = O    --easiest solution: start another iterator for these AD o's displayed on a BC year parent end elseif o <= 0 then --parentAD looking at BC side BC = ' '..BCe o = math.abs(o - 1) --skip o = 0 (DNE) end if BC ~= '' and nord <= 5 then --only show 'BC' for parent ords <= 5: saves room, easier to read, BCdisp = ' '..BCe         --and 6 is the first/last nav ord that doesn't need a disambiguator; end                           --the center/parent ord will always show BC, so no need to show it another 10x --populate left/right navo local oth = p.addord(o) local osign = o --use o for display & osign for logic if BC ~= '' then osign = -osign end local hidden = ' '..oth..' ' if temporal then --e.g. "3rd-century BC" local lastpart = lastpartNoBC --lest we recursively add multiple "BC"s if BC ~= '' then lastpart = string.gsub(lastpart, temporal, temporal..BC) --replace BC if needed end local catlink = catlinkfollowr( frame, firstpart..' '..oth..tspace..lastpart, oth..BCdisp ) if (minord <= osign) and (osign <= maxord) then if catlink.rtarget then --a {{Category redirect}} was followed trackcat(23, 'Navseasoncats nordinal redirected') end navo = navo..navcenter(i, catlink) else navo = navo..'*'..hidden..'\n' if listall then tlistall[#tlistall] = tlistall[#tlistall]..' ('..hidden..')' end end elseif BC == '' and minord <= osign and osign <= maxord then --e.g. >= "1st parliament" local catlink = catlinkfollowr( frame, firstpart..' '..oth..tspace..lastpart, oth ) if catlink.rtarget then --a {{Category redirect}} was followed trackcat(23, 'Navseasoncats nordinal redirected') end navo = navo..navcenter(i, catlink) else --either out-of-range (hide), or non-temporal + BC = something might be wrong (2nd X parliament BC?); handle exceptions if/as they arise navo = navo..'*'..hidden..'\n' end i = i + 1 end isolatedcat if listall then return listalllinks else return navo..'|}' end end

--========================={{ nav_wordinal  }}=============================

local function nav_wordinal( frame, firstpart, word, lastpart, minimumword, maximumword, ordinal, frame ) --Module:ConvertNumeric.numeral_to_english flags: --  ordinal == 'on': 'second' is output instead of 'two' --  ordinal ~= 'on': 'two' is output instead of 'second' local ord2eng = require('Module:ConvertNumeric').numeral_to_english local eng2ord = require('Module:ConvertNumeric').english_to_ordinal local th = 'th' if ordinal ~= 'on' then th = '' eng2ord = require('Module:ConvertNumeric').english_to_numeral end local sc = string.match(word, '^%u') --sentence-case check local lc = string.lower(word) --operate on/with lc, and restore any sc later local nord = eng2ord(lc) local case = nil if sc then case = 'U' end local lspace = ' ' --assume a leading space (most common) local tspace = ' ' --assume a trailing space (most common) if string.match(firstpart, '[%-%(]$') then lspace =  end --DNE for "Straight-eight engines"-type cats	if string.match(lastpart, '^[%-%)]' ) then tspace =  end --DNE for "Nine-cylinder engines"-type cats --sterilize min/max local minword = 1 local maxword = 99 if minimumword then local num = tonumber(minimumword) if num and 0 < num and num < maxword then minword = num else local ord = eng2ord(minimumword) if 0 < ord and ord < maxword then minword = ord end end end if maximumword then local num = tonumber(maximumword) if num and 0 < num and num < maxword then maxword = num else local ord = eng2ord(maximumword) if 0 < ord and ord < maxword then maxword = ord end end end if minword > nord then minword = nord end if maxword < nord then maxword = nord end --begin navwordinal local navw = '{| class="toccolours hlist" style="text-align: center; margin: auto;"\n'..'|\n' local i = -5 --nav position while i <= 5 do		local n = nord + i		if n >= 1 then local nth = p.addord(n) if ordinal ~= 'on' then nth = n end if i ~= 0 then --left/right navw local frame_args = frame:newChild{ args = { n, ord = ordinal, case = case } } --easier to do this than modify Module:ConvertNumeric local w = ord2eng( frame_args ) local catlink = catlinkfollowr( frame, firstpart..lspace..w..tspace..lastpart, nth ) if minword <= n and n <= maxword then if catlink.rtarget then --a {{Category redirect}} was followed trackcat(24, 'Navseasoncats wordinal redirected') end navw = navw..'*'..catlink.navelement..'\n' else local hidden = ' '..nth..' ' navw = navw..'*'..hidden..'\n' if listall then tlistall[#tlistall] = tlistall[#tlistall]..' ('..hidden..')' end end else --center navw navw = navw..'*'..nth..'\n' end else navw = navw..'* '..'0'..th..' \n' end i = i + 1 end isolatedcat if listall then return listalllinks else return navw..'|}' end end

--==========================={{ find_var  }}===============================

local function find_var( pn ) --Extracts the variable text (e.g. 2015, 2015–16, 2000s, 3rd, III, etc.) from a string, --and returns { ['vtype'] = <'year'|'season'|etc.>,  = <2015|2015–16|etc.> } local pagename = currtitle.text if pn and pn ~= '' then pagename = pn	end local cpagename = 'Category:'..pagename --limited-Lua-regex workaround local d_season = mw.ustring.match(cpagename, ':(%d+s).+%(%d+[–-]%d+%)') --i.e. "1760s in the Province of Quebec (1763–1791)" local y_season = mw.ustring.match(cpagename, ':(%d+) .+%(%d+[–-]%d+%)') --i.e. "1763 establishments in the Province of Quebec (1763–1791)" local e_season = mw.ustring.match(cpagename, '%s(%d+[–-])$') or --irreg; ending unknown, e.g. "Members of the Scottish Parliament 2021–" mw.ustring.match(cpagename, '%s(%d+[–-]present)$') --e.g. "UK MPs 2019–present" local season  = mw.ustring.match(cpagename, '[:%s%(](%d+[–-]%d+)[%)%s]') or --split in 2 b/c you can't frontier '$'/eos? mw.ustring.match(cpagename, '[:%s](%d+[–-]%d+)$') local tvseason = mw.ustring.match(cpagename, 'season (%d+)') or					 mw.ustring.match(cpagename, 'series (%d+)') local nordinal = mw.ustring.match(cpagename, '[:%s](%d+[snrt][tdh])[-%s]') or					 mw.ustring.match(cpagename, '[:%s](%d+[snrt][tdh])$') local decade  = mw.ustring.match(cpagename, '[:%s](%d+s)[%s-]') or					 mw.ustring.match(cpagename, '[:%s](%d+s)$') local year    = mw.ustring.match(cpagename, '[:%s](%d%d%d%d)%s') or --prioritize 4-digit years mw.ustring.match(cpagename, '[:%s](%d%d%d%d)$') or					 mw.ustring.match(cpagename, '[:%s](%d+)%s') or					 mw.ustring.match(cpagename, '[:%s](%d+)$') or					 --expand/combine exceptions below as needed mw.ustring.match(cpagename, '[:%s](%d+)-related') or					 mw.ustring.match(cpagename, '[:%s](%d+)-cylinder') or mw.ustring.match(cpagename, '[:%-VW](%d+)%s') --e.g. "Straight-8 engines" local roman   = mw.ustring.match(cpagename, '%s([IVXLCDM]+)%s') local found   = d_season or y_season or e_season or season or tvseason or					 nordinal or decade or year or roman if found then if string.match(found, '%d%d%d%d%d') == nil then --return in order of decreasing complexity/least chance for duplication if nordinal and season --i.e. "18th-century establishments in the Province of Quebec (1763–1791)" then return { ['vtype'] = 'nordinal', ['v'] = nordinal } end if d_season then return { ['vtype'] = 'decade',  ['v'] = d_season } end if y_season then return { ['vtype'] = 'year',    ['v'] = y_season } end if e_season then return { ['vtype'] = 'ending',  ['v'] = e_season } end if season  then return { ['vtype'] = 'season',   ['v'] = season   } end if tvseason then return { ['vtype'] = 'tvseason', ['v'] = tvseason } end if nordinal then return { ['vtype'] = 'nordinal', ['v'] = nordinal } end if decade  then return { ['vtype'] = 'decade',   ['v'] = decade   } end if year    then return { ['vtype'] = 'year',     ['v'] = year     } end if roman   then return { ['vtype'] = 'roman',    ['v'] = roman    } end end else --try wordinals ('zeroth' to 'ninety-ninth' only) local eng2ord = require('Module:ConvertNumeric').english_to_ordinal local split = mw.text.split(pagename, ' ') for i=1, #split do			if eng2ord(split[i]) > -1 then return { ['vtype'] = 'wordinal', ['v'] = split[i] } end end --try English numerics ('one'/'single' to 'ninety-nine' only) local eng2num = require('Module:ConvertNumeric').english_to_numeral local split = mw.text.split(pagename, '[%s%-]') --e.g. "Nine-cylinder engines" for i=1, #split do			if eng2num(split[i]) > -1 then return { ['vtype'] = 'enumeric', ['v'] = split[i] } end end end errors = p.errorclass('Function find_var can\'t find the variable text in category "'..pagename..'".') return { ['vtype'] = 'error', ['v'] = p.failedcat(errors, 'V') } end

--========================================================================== --                                 Main --==========================================================================

function p.navseasoncats( frame ) --arg checks & handling local args = frame:getParent.args checkforunknownparams(args)      --for template args checkforunknownparams(frame.args) --for #invoke'd args local cat = args['cat']                --'testcase' alias for catspace local list = args['list-all-links']    --debugging utility to output all links & followed #Rs local follow = args['follow-redirects'] --default 'yes' local testcase   = args['testcase'] local testcasegap = args['testcasegap'] local minimum = args['min'] local maximum = args['max'] local skip_gaps = args['skip-gaps'] --apply args local pagename = testcase or cat or currtitle.text local testcaseindent = '' if testcasecolon == ':' then testcaseindent = '\n::' end if follow and follow == 'no' then followRs = false end if list and list == 'yes' then listall = true end if skip_gaps and skip_gaps == 'yes' then skipgaps = true trackcat(26, 'Navseasoncats using skip-gaps parameter') end --ns checks if currtitle.nsText == 'Category' then if cat and cat ~= '' then trackcat(1, 'Navseasoncats using cat parameter') end if testcase and testcase ~= '' then trackcat(2, 'Navseasoncats using testcase parameter') end elseif currtitle.nsText == '' then trackcat(30, 'Navseasoncats in mainspace') end --find the variable parts of pagename local findvar = find_var(pagename) if findvar.vtype == 'error' then --basic format error checking in find_var return findvar.v..table.concat(ttrackingcats) end local start = string.match(findvar.v, '^%d+') --the rest is static local findvar_escaped = string.gsub( findvar.v, '%-', '%%%-') local firstpart, lastpart = string.match(pagename, '^(.-)'..findvar_escaped..'(.*)$') if findvar.vtype == 'tvseason' then --double check for cases like '30 Rock (season 3) episodes' firstpart, lastpart = string.match(pagename, '^(.-season )'..findvar_escaped..'(.*)$') if firstpart == nil then firstpart, lastpart = string.match(pagename, '^(.-series )'..findvar_escaped..'(.*)$') end end firstpart = mw.text.trim(firstpart or '') lastpart = mw.text.trim(lastpart or '') --call the appropriate nav function, in order of decreasing popularity if findvar.vtype == 'year' then    --e.g. "500", "2001"; nav_year..nav_decade; ~75% of cats local nav1 = nav_year( frame, firstpart, start, lastpart, minimum, maximum )..testcaseindent..table.concat(ttrackingcats) local dec = math.floor(findvar.v/10) local decadecat = nil local firstpart_dec = firstpart if firstpart_dec ~= '' then firstpart_dec = firstpart_dec..' the' elseif firstpart_dec == 'AD' and dec <= 1 then firstpart_dec = '' if dec == 0 then dec = '' end end local decade = dec..'0s ' decadecat = mw.text.trim( firstpart_dec..' '..decade..lastpart ) local exists = catexists(decadecat) if exists then navborder = false trackcat(28, 'Navseasoncats year and decade') local nav2 = nav_decade( frame, firstpart_dec, decade, lastpart, minimum, maximum )..testcaseindent..table.concat(ttrackingcats) return nav1nav2( nav1, nav2 ) elseif ttrackingcats[16] ~= '' then --nav_year isolated; check nav_hyphen (e.g. UK MPs 1974, Moldovan MPs 2009, etc.) local hyphen = '–' local finish = start local nav2 = nav_hyphen( frame, start, hyphen, finish, firstpart, lastpart, minimum, maximum, testcasegap )..testcaseindent..table.concat(ttrackingcats) if ttrackingcats[16] ~= '' then return nav1 --still isolated; rv to nav_year else return nav2 end else --regular nav_year return nav1 end elseif findvar.vtype == 'decade' then  --e.g. "0s", "2010s"; nav_decade..nav_nordinal; ~12% of cats local nav1 = nav_decade( frame, firstpart, start, lastpart, minimum, maximum )..testcaseindent..table.concat(ttrackingcats) local decade = tonumber(string.match(findvar.v, '^(%d+)s')) local century = math.floor( ((decade-1)/100) + 1 ) --from {{CENTURY}} if century == 0 then century = 1 end --no 0th century if string.match(decade, '00$') then century = century + 1 --'2000' is in the 20th, but the rest of the 2000s is in the 21st end local clastpart = ' century '..lastpart local centurycat = mw.text.trim( firstpart..' '..p.addord(century)..clastpart ) local exists = catexists(centurycat) if not exists then --check for hyphenated century clastpart = '-century '..lastpart centurycat = mw.text.trim( firstpart..' '..p.addord(century)..clastpart ) exists = catexists(centurycat) end if exists then navborder = false trackcat(29, 'Navseasoncats decade and century') local nav2 = nav_nordinal( frame, firstpart, century, clastpart, minimum, maximum )..testcaseindent..table.concat(ttrackingcats) return nav1nav2( nav1, nav2 ) else return nav1 end elseif findvar.vtype == 'nordinal' then --e.g. "1st", "99th"; ~7.5% of cats return nav_nordinal( frame, firstpart, start, lastpart, minimum, maximum )..testcaseindent..table.concat(ttrackingcats) elseif findvar.vtype == 'season' then  --e.g. "1–4", "1999–2000", "2001–02", "2001–2002", "2005–2010", etc.; ~5.25% local hyphen, finish = mw.ustring.match(findvar.v, '%d([–-])(%d+)') --ascii 150 & 45 (ndash & keyboard hyphen); mw req'd		return nav_hyphen( frame, start, hyphen, finish, firstpart, lastpart, minimum, maximum, testcasegap )..testcaseindent..table.concat(ttrackingcats) elseif findvar.vtype == 'tvseason' then --e.g. "1", "15" but preceded with "season" or "series"; <1% of cats return nav_tvseason( frame, firstpart, start, lastpart, maximum )..testcaseindent..table.concat(ttrackingcats) --"minimum" defaults to 1 elseif findvar.vtype == 'wordinal' then --e.g. "first", "ninety-ninth"; <<1% of cats local ordinal = 'on' return nav_wordinal( frame, firstpart, findvar.v, lastpart, minimum, maximum, ordinal, frame )..testcaseindent..table.concat(ttrackingcats) elseif findvar.vtype == 'enumeric' then --e.g. "one", "ninety-nine"; <<1% of cats local ordinal = 'off' return nav_wordinal( frame, firstpart, findvar.v, lastpart, minimum, maximum, ordinal, frame )..testcaseindent..table.concat(ttrackingcats) elseif findvar.vtype == 'roman' then   --e.g. "I", "XXVIII"; <<1% of cats return nav_roman( frame, firstpart, findvar.v, lastpart, minimum, maximum )..testcaseindent..table.concat(ttrackingcats) elseif findvar.vtype == 'ending' then  --e.g. "2021–" (irregular; ending unknown); <<<1% of cats local hyphen, finish = mw.ustring.match(findvar.v, '%d([–-])present$'), -1 --ascii 150 & 45 (ndash & keyboard hyphen); mw req'd		if hyphen == nil then hyphen, finish = mw.ustring.match(findvar.v, '%d([–-])$'), 0 --0/-1 are hardcoded switches for nav_hyphen end return nav_hyphen( frame, start, hyphen, finish, firstpart, lastpart, minimum, maximum, testcasegap )..testcaseindent..table.concat(ttrackingcats) else                                --malformed errors = p.errorclass('Failed to determine the appropriate nav function from malformed season "'..findvar.v..'". ') return p.failedcat(errors, 'N')..table.concat(ttrackingcats) end end

return p