Entity Count Detector

function getEntityCount(range, x, y, z, entity)
  local t = peripheral.find("EntityDetector")
  if not t then
    error("No EntityDetector detected !")
  end

  if not entity then
    return false
  end

  local tEntities = {}
  local nEntityCount = 0
  local f = t.getEntityList(range, x, y, z)

  for k, v in pairs(f) do
    if v.type == entity then
      nEntityCount = nEntityCount + 1
      table.insert(tEntities, v.type)
    end
  end

  return nEntityCount, tEntities
end