View source for Module:Used by

local p = {}

function common_string(args)
  return mw.getCurrentFrame():expandTemplate{title='Common string', args=args}
end

function get_args(frame)
    local args = {}
    for _, arg in ipairs(frame.args) do
        table.insert(args, arg)
    end
    if #args > 0 then return args end

    for _, arg in ipairs(frame:getParent().args) do
        table.insert(args, arg)
    end

    return args
end

function p.classes(frame)
    local args = get_args(frame)

    if args[1] == 'all' then
        return common_string{'infobox-used-by-all'}
    elseif args[1] == 'all-except' then
        table.remove(args, 1) -- Remove the 'all-except' argument
        assert(#args >= 1, "You must provide at least 1 class when using 'all-except'.")
        assert(#args <= 3, "You must provide at most 3 classes when using 'all-except'.")
        return common_string{'infobox-used-by-all-except-' .. #args, unpack(args)}
    else
        assert(#args >= 1, "You must provide at least 1 class when using this function.")
        assert(#args <= 5, "You must provide at most 5 classes when using this function.")
        return common_string{'infobox-used-by-' .. #args, unpack(args)}
    end
end

return p
Description	What you type	What you get
Italic	''Italic text''	Italic text
Bold	'''Bold text'''	Bold text
Bold & italic	'''''Bold & italic text'''''	*Bold & italic text*