Why do the docs all put single variables values in string templates?

Here is an example from your docs

resource "aws_sns_topic_subscription" "user_updates_sqs_target" {
  topic_arn = "${aws_sns_topic.user_updates.arn}"
  protocol  = "sqs"
  endpoint  = "${aws_sqs_queue.user_updates_queue.arn}"
}

I have tried it out and this works, too:

resource "aws_sns_topic_subscription" "user_updates_sqs_target" {
  topic_arn = aws_sns_topic.user_updates.arn
  protocol  = "sqs"
  endpoint  = aws_sqs_queue.user_updates_queue.arn
}

Why do all the examples use “${var}” instead of just var? Is that to handle spaces or some other character? I find the latter more straightforward to read but want to check before I standardize on it.

THanks

The ${} is the pre 0.12 syntax. It could be a remnant of that. :thinking: