local p = {}
getArgs = require('Module:Arguments').getArgs
builder = mw.html.create()
local div_root = builder
    :tag('div')
    :cssText('float:left;border:2em;width:80%')
    :wikitext('This is div_root in main program\n')
--local cntnt = div_root
local cntnt = builder
    :tag('div')
    :cssText('text-align:left; padding:1em; font-size:95%; margin:2em; background:yellow;width:50%')
    :wikitext('that is cntnt in main program\n')

function p.getArgNums(frame)
    -- Returns a table containing the numbers of the arguments that exist
    -- for the specified prefix. For example, if the prefix was 'data', and
    -- 'data1', 'data2', and 'data5' exist, it would return {1, 2, 5}.
    local nums = {}
    local prefix='a'
    cntnt:wikitext('Das ist nun cntnt innerhalb GetArgsNums<br>')
    for k, v in pairs(frame.args) do
        local num = tostring(k):match('^' .. prefix .. '([1-9]%d*)$')
        if num then table.insert(nums, tonumber(num)) end
        cntnt:wikitext( 'Key= ' .. k .. ' Value= ' .. v .. '<br/>' )
    end
    -- Initially the table nums was returned
    table.sort(nums)
    -- I still don't know what to do with a table, so I return cntnt
    -- error: mv.log('testen der Funktion mw.log innerhalb einer Funktionsaufruf\n')
    cntnt:wikitext('Das ist nun cntnt am Ende von GetArgsNums\n')
    return tostring (cntnt)
end

function p.main (frame)
    local sOutputText = ""
    cntnt:wikitext('here is p.main in cntnt\n')
    div_root.wikitext('here is p.main in div_root\n')
    for iKey,sValue in pairs(frame.args) do 
        sOutputText = sOutputText  .. iKey .. sValue  .. "♣\n"
    end
    div_root:wikitext(sOutputText)
	return tostring(div_root)
end

return p