array index and modulo

["Wesley Smith" <wesley.hoke@...>]

This is a very simple problem, but I'm failing to find an elegant
solution.  I have an array of data that I'm treating as a circular
buffer.  Typically I use modulo to wrap the index to the range of the
buffer, but since Lua arrays start from 1 (and I want to follow this
convention), the modulo operator is not really useful.

for example.

given

local numData = 10
data = {}
for i=1, numData do
    data[i] = newData()
end
currentData = 0

what is a good solution for this function:

function nextData()
    currentData = (currentData+1) % (#data)              --gives [0, #data-1]
    return data[currentData]
end


--I could do this, but is there a better solution?
function nextData()
    currentData = currentData+1
    if(currentData > #data)  currentData = 1   end
    return data[currentData]
end

thanks,
wes