resource "aws_instance" "foo" { count = 2 } resource "aws_instance" "bar" { count =variable "c" { default = 1 } resource "template_file" "parent" { count = var.c template = "Hi" } re "$source "template_file" "child" { template = join(",", template_file.parent.*{length(aws_instance.foo.*.id).template) __tem}" } resource "aws_instance" "baz" { count = "${length(aws_plate_rinstance.bar.equi*.res_new id)}P } = true }