Initialize array of size 0?

Newbies
#1

Curious if it’s possible to initialize an array of size zero. I’m modifying some arrays at runtime and am having a hard time removing an element when only 1 element remains in the array. I could do something like set the last element to a large negative number or something but am curious if this is possible before I go modifying all of my code to support something like that.

On init pass I noticed that some of the conditionally initialized arrays will exist so calling lenarray on them doesn’t seem to throw any errors and simply returns 0. Am looking to do this within an UDO for removing an element so I can return an array of size 0 if there is only 1 element remaining in the array.

Thanks in advance as always

Cheers

#2

Figured I’d post the solution here if anyone is interested, very hacky but hey, it works. I modified one of the UDO’s provided by @joachim from this thread. For the removal and returning of an empty array I just initialize a variable and then put the array initialization in a conditional that will never execute. If you pass in an empty array to the add element functionality it will check for that and then initialize a new array and insert the desired element as the only element in the array.

;Removes an index from from an array and returns new array
opcode arrayremoveindex, i[], i[]i
	iInArr[], iIndx xin
	iA init 1
	if(lenarray(iInArr) == 1) then
		if(iA == 0)then
			iOutArr[] = iInArr
		endif
	else
		iOutArr[]  init       lenarray(iInArr)-1
		iReadIndx  =          0
		 until iReadIndx == iIndx do
		iOutArr[iReadIndx] =  iInArr[iReadIndx]
		iReadIndx  +=         1
		 enduntil
		iReadIndx  +=         1
		 until iReadIndx == lenarray(iInArr) do
		iOutArr[iReadIndx-1] = iInArr[iReadIndx]
		iReadIndx  +=         1
		 enduntil
	endif
			   xout       iOutArr
endop

opcode arrayaddelement, i[], i[]ij
 iInArr[], iEl, iPos xin
 prints "Array length"
if(lenarray:i(iInArr) == -1) then
	iOutArr[] init 1
	iOutArr[0] = iEl
else
 iOutArr[] init lenarray:i(iInArr)+1

 iPos = (iPos == -1) ? lenarray:i(iInArr) : iPos
 iWriteIndx = 0
 iIndxDiff = 0
 while iWriteIndx < lenarray:i(iOutArr) do
  iReadIndx = iWriteIndx - iIndxDiff
  if iWriteIndx == iPos then
   iOutArr[iWriteIndx] = iEl
   iIndxDiff = 1
  else
   iOutArr[iWriteIndx] = iInArr[iReadIndx]
  endif
  iWriteIndx += 1
 od
 endif
 xout iOutArr
endop
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