Module:Buffer

--[[============================= This Module was written by English wikipedia User:Codehydro All methods were developed independently and any resemblance to other string buffer libraries would be coincidental.

Licensed under Creative Commons Attribution-ShareAlike 3.0 Unported License https://en.wikipedia.org/wiki/Wikipedia:Text_of_Creative_Commons_Attribution-ShareAlike_3.0_Unported_License

https://en.wikipedia.org/wiki/Module:Buffer https://en.wikipedia.org/wiki/User:Codehydro

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================--]] return setmetatable({[type] = function(v)		if v and v~=true then--reject nil/boolean; faster than 2 type comparisons			local str = tostring(v)			if str~=v and str=='table' then return table.concat(v) end			return str~='' and str or nil		end	end,	[select] = function(n, ...)		local seps, meta = {select(2, ...)}		if type(seps[#seps])=='table' then			meta = rawset(table.remove(seps), '__index', function(t, i) return meta[1] end)			setmetatable(seps, meta)		end		return ..., seps	end,	__index = {		_ = function(self, v, ...)			local at, raw			if select('#', ...)==1 and ...==not not... then raw = ...			else at, raw = ... end			if raw then self[rawset] = math.huge else v = getmetatable(self)[type](v) end			if v or raw then				if at then					if tostring(at)==at then at = #self + at end					if at < 1 then self[rawset] = math.huge					elseif at > #self + 1 then self[rawset] = self[rawset] and math.max(at, self[rawset]) or at end end self.last_concat = table.insert(self, select(at and 1 or 2, at, v)) end return self end, _nil = function(self, at, v2) if v2~=true and v2~=false then--faster than type(v2) ~= 'boolean' self.last_concat = nil if at=='0' or at==nil then self[#self] = v2					if v2 then self[rawset] = math.huge end else if tostring(at)==at then at = #self + at end if v2 or self[rawset] or at #self + 1 then self[at], self[rawset] = v2, math.huge else table.remove(self, at) end end end return self end, _all = function(self, t, valKey) for k, v in getmetatable(self).__pairs(t) do self:_mix(v) end if valKey then for k, v in getmetatable(self).__pairs(t, false) do					if tonumber(v) then self:_(k, v) end end end return self end, _mix = function(self, v, a) return v and ((type(v)~='table' or getmetatable(v)) and self._ or self._all)(self, v, a) or self end,--internal helper, do not list in doc _str = function(self, ...) return getmetatable(self).__tostring(self, ...) end, _in = function (self, ...) return rawset(getmetatable(self)(...), next, self) end,--Module:Buffer objects use [next] rather than 'parent' to avoid traversal by mw.html.allDone _out = function(self, ...) if self[next] then local n, parent = select('#', ...), self[next] if n > 1 then local k, outs, seps = 1, getmetatable(self)[select](n, ...) while outs > 0 do						parent:_(self(seps[k])) self, parent, k = parent, parent[next], k + 1 outs = parent and outs - 1 or 0 end else return parent:_(self(...)) end end return self[next] or self end, _c = function(self, clear, copy) assert(type(clear)=='table', copy and				"Buffer:_c(clear, copy) only accepts tables for arg 'clear'."				or "Two possible causes: 1) Called Buffer:_c(clear, copy) without colon, or 2) Type of 'clear' is not 'table'."			) for k in next, clear do clear[k] = nil end local meta, copyMeta, copyType = getmetatable(self) if copy then if type(copy)=='table' then for k, v in next, copy do clear[k] = type(v)=='table' and mw.clone(v) or v end clear[rawset] = clear[rawset] or math.huge copyMeta = getmetatable(copy) if copyMeta then if not buffHTMLmeta then meta:_inHTML end if copyMeta==buffHTMLmeta[mw.html] then copyMeta = buffHTMLmeta setmetatable(clear.nodes, meta) end end elseif meta[type](copy) then clear[1] = copy end end setmetatable(clear, copyMeta or meta) return self end, _parent = function(self, s, outs, ...) return self:_(outs and self[next]:_str(s, outs, ...) or self[next](s)) end, getParent = function(self, ...) return (assert(self, ' (:function, not .function)')[next] or rawset(rawset(self, next, getmetatable(self))[next], require, {self})):_(...) end, _inHTML = function(self, ...) local HTML, meta = mw.html.create(...), getmetatable(self) if not rawget(_G, 'buffHTMLmeta') then local mwHTMLmeta = getmetatable(mw.html.create) buffHTMLmeta, mwHTMLfunc = rawset(mw.clone(mwHTMLmeta), mw.html, mwHTMLmeta), mwHTMLmeta.__index for k, v in next, { [rawget] = function(HTML, Buffer, ...) buffHTMLmeta[require] = HTML if ... then return select('#', ...)==1 and Buffer:_(...) or assert(Buffer[...], ('" %s " does not match any Module:Buffer function'):format(tostring(...)))(Buffer, select(2, ...)) end return Buffer end, getParent = function(HTML, ...) return HTML[rawget](HTML, HTML:allDone[next], ...) end,--return to buffer that created it					getBuffer = function(HTML, ...) return HTML[rawget](HTML, buffHTMLmeta[next], ...) end,--return to last buffer used _out = function(HTML, ...) return HTML:getParent:_(HTML):_out(...) end, _inv = function(HTML, s, outs, ...) return HTML.nodes:_(outs and HTML:getParent:_str(s, outs, ...) or HTML:getParent(s)) end } do buffHTMLmeta.__index[k] = v end if new_G then for k, v in pairs(gfuncs) do buffHTMLmeta.__index[k] = v end gfuncs = nil end local mbpairs, outFuncs, htmlArg, nonSelf, spinach = meta.__pairs, {}, {parent = true, selfClosing = true, tagName = true}, {tag = true, done = true, allDone = true} spinach = {--spinach makes html.nodes buffer... get it?... [rawset] = math.huge, _out = function(nodes, ...) return nodes:getParent('_', nodes:getHTML):_out(...) end, _add = function(nodes, t)--children are unenhanced local HTML, nodeFunc = nodes[next], buffHTMLmeta[require].nodes for k, v in mbpairs(t) do buffHTMLmeta.__call(HTML, v~=true and v) end for k, v in mbpairs(t, false) do							if htmlArg[k] then HTML[k] = v							elseif v and v~=true then if nonSelf[k] then if k=='tag' then if tostring(v)==v then mwHTMLfunc.tag(HTML, v)										elseif v[1] and v[1]~=true then local tag = mwHTMLfunc.tag(HTML, v[1]) setmetatable(nodeFunc._add(rawset(setmetatable(tag.nodes, meta), next, tag), v), nil)[1], tag.nodes[next] = false else nodeFunc._add(HTML.nodes, v) end else buffHTMLmeta.__call(mwHTMLfunc[k](HTML), v) end--k = done/allDone elseif mwHTMLfunc[k] then if k=='node' or type(v)~='table' then mwHTMLfunc[k](HTML, v)									else for _, y in mbpairs(v) do											if y and y~=true then mwHTMLfunc[k](HTML, y) end end for x, y in mbpairs(v, false) do											if y and y~=true then mwHTMLfunc[k](HTML, x, y) end end end else nodeFunc[k](HTML.nodes, v) end end end return nodes end }				function makeNodesBuffer(HTML) local nodes = setmetatable(HTML.nodes, meta) nodes[next], nodes.parent = HTML, HTML for k, v in next, buffHTMLmeta.__index do						nodes[k] = rawset(outFuncs, k, outFuncs[k] or function(nodes, ...) return v(nodes[next], ...) end)[k] end for k, v in next, spinach do nodes[k] = v end nodes._inHTML, nodes._build = nodes.tag end for k in next, nonSelf do--any HTML objects returned by these funcs will be granted Module:Buffer enhancements local func = mwHTMLfunc[k] buffHTMLmeta.__index[k] = function(t, ...) local HTML = func(t, ...) if not (HTML.selfClosing or HTML[next]) then makeNodesBuffer(setmetatable(rawset(HTML, next, t), buffHTMLmeta)) end return HTML end end for k, v in next, {--add new Buffer object functions getHTML = function(self, ...) buffHTMLmeta[next] = self if ... then if type(...)=='table' then return buffHTMLmeta[require](...) else return assert(buffHTMLmeta[require][...], ('" %s " does not match any mw.html function'):format(tostring(...)))(buffHTMLmeta[require], select(2, ...)) end end return buffHTMLmeta[require] end, _html = function(self, ...) return self:_(self:getHTML, ...) end } do meta.__index[k] = v end buffHTMLmeta.__call = function(h, ...) return ... and ('table'==type(...) and spinach._add or h.nodes._)(h.nodes, ...) or h.nodes end end makeNodesBuffer(setmetatable(HTML, buffHTMLmeta)) rawset(setmetatable(HTML, rawset(buffHTMLmeta, require, HTML)), next, self) return self:getHTML end, _build = function (self, nodes) return table.insert(nodes, self) end--for compatibility with regular mw.html objects },	__call = function(t, ...) local t2 = t[rawset] and t[rawset] > #t and getmetatable(t):_all(t) or t		if select('#', ...)==0 then return rawset(t, 'last_concat', t.last_concat or table.concat(t2)).last_concat end return table.concat(t2, ...) or '' end, __tostring = function(t, ...) if type(t)~='table' then return t end local n, r = select('#', ...), getmetatable(t) if n > 1 then local k, outs, seps = 2, r[select](n, ...) r = r(t(seps[1])) while outs > 1 do				r:_(t[next](seps[k]), 1) t, k = t[next], k + 1 outs = t[next] and outs - 1 or 0 end return table.concat(r, seps[k]) or '' end return t(...) end, __concat = function(a, b, Buffer) if Buffer then return error end Buffer = getmetatable(a) local us, them = pcall(Buffer and Buffer.__concat, false, next, 1) if not us or them~=error then Buffer = getmetatable(b) end return Buffer:_all{a, b} end, __pairs = function(t, ...)--pairs always iterates in order if not map_i then local mk = {__mode='k'} map_i, map_n, map_o = setmetatable({}, mk), setmetatable({}, mk), setmetatable({}, mk)--reduces table lookups function mBuffIter(t, i) i = map_i[t][nil==i and 1 or map_n[t][i]] return i, t[i] end function mBuffOther(t, i) i = map_o[t][nil==i and 1 or map_o[t][i]] return i, t[i] end function mBuffMap(t) local ti, tn, to, n = {}, {}, {}, #t--reduces table lookups map_i[t], map_n[t], map_o[t] = ti, tn, to				for k = 1, n do					table.insert(ti, k)					tn[k] = k + 1 end if n==0 or next(t, n)~=nil then local start = next(t)==1 and n or nil for k, v in next, t, start do						if tn[k] then--no op, since: t={[2]=1,[1]=2}; #t => 2; next(t,#t) => 1,2 elseif tonumber(k)==k then table.insert(ti, k)						elseif k~=t and v~=t then table.insert(to, k)							to[k] = #to + 1 end end if #ti~=n then table.sort(ti) for k, v in next, ti do tn[v] = k + 1 end end end end end if select('#', ...)==0 or ...==true then mBuffMap(t) end return ...==nil and mBuffIter or mBuffOther, t	end, __ipairs = pairs },{__tostring = functionreturn''end, __call = function(self, ...) if not rawget(_G, 'libFunc') then--adds string and mw libraries; also add global functions if passed; rawget avoids error when reading nil global rawset(_G, 'libFunc', {__call = function(t, self, ...) return t[1](type(self)~='table' and self or self:_str, ...) end}) for _, library in ipairs{mw.text, string, mw.ustring} do for k, func in pairs(library) do self.__index[library==mw.ustring and k .. '_' or k] = setmetatable({func}, libFunc) end end rawset(_G, 'new_G', ... and type(...)=='table' and (...)._G==... and ...~=_G and (...).mw and (...).mw.log==mw.log and ...) if new_G then rawset(_G, 'gfuncs', {--stored as global for Buffer:_inHTML					_G = function(self, name, var)						if rawget(new_G, name) then 							local metaG = getmetatable(new_G)							if not metaG then								metaG = {__index = {}}								setmetatable(new_G, metaG)							end							metaG.__index[name] = new_G[name]						end						new_G[name] = var or self						return self					end,					_R = function(self, name, var) new_G[name] = var return self end,					_B = function(self, var) return var or var~=false and self end				}) for k, v in pairs(gfuncs) do self.__index[k] = v end end end if new_G and ... and (...)==new_G then--avoid error when passing _G to buffer a second time local new, name = setmetatable({}, self), select(2, ...) if name and type(name)=='string' then new_G[name] = new end return new end return setmetatable({}, self):_(...) end, __index = function(t, i)		return function(...) return t.__index[i](t, select(2,...)) end end })