--- Entrypoint templating wrapper for Scribunto packages. --  The module generates an entrypoint function that can execute Scribunto --  package calls in the template context. This allows a package to support --  both direct and template invocations. --   --  @script             entrypoint --  @release            stable --  @author             [[User:8nml|8nml]] --  @param              {table} package Scribunto package. --  @error[85]          {string} 'you must specify a function to call' --  @error[91]          {string} 'the function you specified did not exist' --  @error[opt,95]      {string} '$2 is not a function' --  @return             {function} Template entrypoint - @{main}. --  @note               Parent frames are not available in Entrypoint's --                      `frame`. This is because recursive (grandparent) --                      frame access is impossible in legacy Scribunto --                      due to [[mw:Manual:Parser#Empty-argument expansion --                      cache|empty-argument expansion cache]] limitations. --  @note               As Entrypoint enables template access rather than --                      a new extension hook, it does not work with named --                      numeric parameters such as `1=` or `2=`. This may --                      result in unexpected behaviour such as Entrypoint --                      and module errors.  --- Stateless, sequential Lua iterator. --  @function           inext --  @param              {table} t Invariant state to loop over. --  @param              {number} i Control variable (current index). --  @return[opt]        {number} Next index. --  @return[opt]        {number|string|table|boolean} Next value. --  @see                [[github:lua/lua/blob/v5.1.1/lbaselib.c#L247]] local inext = select(1, ipairs{})  --- Check for MediaWiki version 1.25. --  The concurrent Scribunto release adds a type check for package functions. --  @variable           {boolean} func_check --  @see                [[mw:MediaWiki 1.24/wmf7#Scribunto]] local func_check = tonumber(mw.site.currentVersion:match('^%d+.%d+')) >= 1.25  --- MediaWiki error message getter. --  Mimics Scribunto error formatting for script errors.  --  @function           msg --  @param              {string} key MediaWiki i18n message key. --  @param[opt]         {string} fn_name Name of package function. --  @return             {string} Formatted lowercase message. --  @local local function msg(key, fn_name)     return select(1, mw.message.new(key)         :plain()         :match(':%s*(.-)[.۔。෴։።]?$')         :gsub('^.', mw.ustring.lower)         :gsub('$2', fn_name or '$2')     ) end  --- Template entrypoint function generated by this module. --  @function           main --  @param              {Frame} frame Scribunto frame in module context. --  @return             {string} Module output in template context. return function(package) return function(f)     local frame = f:getParent()      local args_mt = {}     local arg_cache = {}      args_mt.__pairs = function()         return next, arg_cache, nil     end     args_mt.__ipairs = function()         return inext, arg_cache, 0     end     args_mt.__index = function(t, k)         return arg_cache[k]     end      for key, val in pairs(frame.args) do         arg_cache[key] = val     end     local fn_name = table.remove(arg_cache, 1)      f.args = setmetatable({}, args_mt)     frame.args = setmetatable({}, args_mt)      if not fn_name then         error(msg('scribunto-common-nofunction'))     end      fn_name = mw.text.trim(fn_name)      if not package[fn_name] then         error(msg('scribunto-common-nosuchfunction', fn_name))     end      if func_check and type(package[fn_name]) ~= 'function' then         error(msg('scribunto-common-notafunction', fn_name))     end      return package[fn_name](frame) end end