Cloudformation vs Terraform

subnet.cf.yaml

resources:
  app_subnet_1:
    Type: "AWS::EC2::Subnet"
    Properties:
      AvailabilityZone: !Select: [ 0, !Ref subnet_azs ] 
      CidrBlock: !Select: [ 0, !Ref subnet_cidrs ]
      Tags:
        - Key: environment
          Value: !Ref workspace
        - Key: division
          Value: tech
        - Key: Name
          Value: !Sub
            - AppSubnetAZ1-${workspace}
            - { workspace: !Ref workspace }
      VpcId: !Ref vpc_id
  app_subnet_2:
    Type: "AWS::EC2::Subnet"
    Properties:
      AvailabilityZone: !Select: [ 1, !Ref subnet_azs ] 
      CidrBlock: !Select: [ 1, !Ref subnet_cidrs ]
      Tags:
        - Key: environment
          Value: !Ref workspace
        - Key: division
          Value: tech
        - Key: Name
          Value: !Sub
            - AppSubnetAZ2-${workspace}
            - { workspace: !Ref workspace }
      VpcId: !Ref vpc_id
      

subnet.tf

resource "aws_subnet" "app" {
  count             = "${length(var.subnet_cidrs)}"
  vpc_id            = "${var.vpc_id}"
  cidr_block        = "${var.subnet_cidrs[count.index]}"
  availability_zone = "${var.subnet_azs[count.index]}"

  tags {
    environment         = "${terraform.workspace}"
    division            = "tech"
    Name                = "AppSubnetAZ${count.index+1}-${terraform.workspace}"
  }
}