terraform在使用元素时给我函数调用错误

Question

嗨，我一直遇到错误。

我得到的错误：

Error: Error in function call

  on vpc.tf line 57, in resource "aws_route_table_association" "private_subnet":
  57:   subnet_id      = element(aws_subnet.private.*.id, count.index)
    |----------------
    | aws_subnet.private is empty tuple
    | count.index is 1

Call to function "element" failed: cannot use element function with an empty
list.

variable "private_subnets_cidrs" {
  description = "The CIDR range for the private subnets"
  type        = list(string)
}

我添加了我的子网和路由表关联资源，供您检查。

resource "aws_subnet" "private" {
  count                           = local.max_subnet_length
  vpc_id                          = aws_vpc.proxy_vpc.id
  cidr_block                      = var.private_subnets_cidrs[count.index]
  availability_zone               = element(var.azs, count.index)
}

private_subnets_cidrs = ["10.9.*.*/2*", "10.9.*.*/2*"]

resource "aws_route_table_association" "private_subnet" {
  count          = length(var.private_subnets_cidrs) > 0 ? length(var.private_subnets_cidrs) : 0
  subnet_id      = element(concat(aws_subnet.private.*.id), count.index)
  route_table_id = element(aws_route_table.private.*.id, count.index)
}

请有人可以帮助我。 我该如何解决？我希望能够将每个子网与每个路由表相关联