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My suggestions, since it's easy for you to measure if there's any effect: 

- local data_i= data[i]
to cache the value, and avoid a number of table accesses (locals are fast) 
- local data_i1= data[i][1]
same thing
- is 'data[i]' a table of two values that do not change? If so, just use it, not making a copy? 



    local data = dataGenerator()

	local subTable = {}
	local subTableBlock = {}
	local subTableType
	
    for i, element in ipairs(data) do

local data_i= data[i]
local data_i1= data_i[1]

        if data_i1 == "<type>" then
			subTableType = data_i[2]
        elseif data_i1 == "</type>" then
        elseif data_i1 == "<block>" then
            subTableBlock =
{Number=data_i[2],Dup=data_i[3]}
        elseif data_i1 == "</block>" then
			subTable[#subTable+1] = subTableBlock
        else
            if trim(data_i[2]) ~= "" then
                subTableBlock[#subTableBlock+1] =

data_i	-- in case it only has [1] and [2]

            end
        end
    end

    return subTable, subTableType

end





On 21.11.2006, at 17.40, Steve Heller wrote:


Unfortunately, my timing runs show that your
suggestion makes no measurable difference. Any other
suggestions would be welcomed.

--- Romulo Bahiense <romulo@icontroller.com.br> wrote:


I believe the problem is not table allocation, but
index access and
length calculation ('#' operator).

Try this one:

function createFieldDataEntriesForOneDataGenerator(
dataGenerator )

     local data = dataGenerator()

     local iSubTable      = 0
     local iSubTableBlock = 0

     local subTable      = {}
     local subTableBlock = {}

     local subTableType

     for i, element in ipairs(data) do
         local a, b, c = element[ 1 ], element[ 2 ],
element[ 3 ]
         if a == "<type>" then
             subTableType = b
         elseif a == "</type>" then
             -- do nothing
         elseif a == "<block>" then
             subTableBlock = {Number=b,Dup=c}
         elseif a == "</block>" then
             iSubTable = iSubTable + 1
             subTable[iSubTable] = subTableBlock
         else
             if trim(b) ~= "" then
                 iSubTableBlock = iSubTableBlock + 1
                 subTableBlock[ iSubTableBlock ] =
{a,b}
             end
         end
     end

     return subTable, subTableType
end

Note that, in this code, 'data[i]' is the same as
'element', because
ipairs return key and value.

--rb