Module:Buffer
From ChaldeanWiki
Documentation for this module may be created at Module:Buffer/doc
--[[=============================
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
=============================--]]
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 < 1 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 = function()return''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
})
