Module:Technical reasons

local mHatnote = require('Module:Hatnote')
local mHatlist = require('Module:Hatnote list')
local mArguments --initialize lazily
local mTableTools = require('Module:TableTools')
local p = {}

function p.technicalReasons (frame)
	mArguments = require('Module:Arguments')
	local args = mArguments.getArgs(frame)
	return p._technicalReasons(args)
end

function p._technicalReasons (args)
	--Gaps are suppressed!
	args = mTableTools.compressSparseArray(args)
	--Return an error if no redirect's provided
	if #args == 0 then
		return mHatnote.makeWikitextError(
			'no redirect provided',
			'Template:Technical reasons'
		)
	end
	local from = 2
	--Suppresses defaulting; every use requires a page or the for-see item
	--doesn't display.
	if #args > 3 and #args % 2 == 0 and
		(#args < 5 or args[#args - 1] ~= 'and') then
			args[#args] = nil
	end
	--if only two args, arg[1] is the use, arg[2] is the page, by evaluation offset.
	if #args == 2 then from = 1 end
	local technicalForm = 'For [[Wikipedia:Naming conventions (technical restrictions)#Forbidden characters|technical reasons]], "%s" redirects here.'
	local forSee --nil by default to concat nicely if not present
	if #args > 1 then forSee = mHatlist._forSee(args, from) end
	local text = table.concat({string.format(technicalForm, args[1]), forSee}, ' ')
	return mHatnote._hatnote(text)
end

return p