Recursive function only generating half of desired outputs

I'm trying to generate all combinations of elements taken from n vectors

   allinputs = {[1 2] [3 4] [5 6] [7 8]}
   inputArray = inputBuilder([],allinputs,1)

I can get this done without recursion but I like this way because it's more extensible for my purposes.

   function inputArray = inputBuilder(currBuild, allInputs, currIdx)

   inputArray = [];
   if currIdx <= length(allInputs)

    for i = 1:length(allInputs{currIdx})
        mybuild = [currBuild allInputs{currIdx}(i)];
        inputArray = [inputArray inputBuilder(mybuild,allInputs,currIdx + 1)];

    end

    if currIdx == length(allInputs)
        inputArray = {inputArray mybuild};
    end

   end
   end

I should be getting a vector of 16 1x4 arrays but I'm missing all the combinations that end with 7

*1 3 5 7

1 3 5 8

*1 3 6 7

1 3 6 8

etc etc... The * indicates what I'm missing in the output, it just comes out as []

Answer 1

[Drew]

Solved it.

   function inputArray = inputBuilder(currBuild, allInputs, currIdx)

    inputArray = [];
    if currIdx <= length(allInputs)

        for i = 1:length(allInputs{currIdx})

            mybuild = [currBuild allInputs{currIdx}(i)];
            inputArray = [inputArray inputBuilder(mybuild,allInputs,currIdx + 1)];

        end
    else
        if isempty(inputArray)
            inputArray = {currBuild};
        else
            inputArray = {inputArray currBuild};
        end
    end

   end