function Structure.StackPush(array, v) TableUtility.ArrayPushBack(array, v) end function Structure.StackPop(array) return TableUtility.ArrayPopBack(array) end function Structure.StackPeek(array) if 0 >= #array then return nil end return array[#array] end function Structure.StackPeekByIndex(array, index) if not (0 < #array and #array >= index) then return nil end return array[#array-index+1] end