Terraform code supports three different syntaxes for comments:

• Single-line comments:
  • # begins a single-line comment, ending at the end of the line.
  • // also begins a single-line comment, as an alternative to #.
• Multi-line comments:
  • /* and */ are start and end delimiters for a comment that might span over multiple lines.

Comments can be placed anywhere in a Terraform configuration file, but they are typically placed at the beginning of a file or before a specific resource. Comments can be used to:

• Document your Terraform code and explain what it does.
• Make your Terraform code more readable and easier to understand.
• Disable or uncomment sections of your Terraform code.

Here are some examples of comments in Terraform code:

# This is a single-line comment.

// This is also a single-line comment.

/*
This is a multi-line comment.
*/

variable "instance_type" {
  type = string
  description = "The type of EC2 instance to launch."
  default = "t2.micro"
}

resource "aws_instance" "example" {
  ami = "ami-06984b521991bb600"
  instance_type = var.instance_type

  tags = {
    Name = "My Example Instance"
  }
}

Explanation:

• # starts a single-line comment, which ends at the end of the line.
• // also starts a single-line comment, as an alternative to #.
• /* starts a multi-line comment, and */ ends it.

The single-line comments in the example are used to document the purpose of the variable and resource blocks. The multi-line comment is used to document the tags that will be applied to the EC2 instance.

Rajesh Kumar

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