Operator ... does not work with variables

[MarkKharitonov]

Terraform Version

C:\temp\terraform\cfg [master]> C:\Users\mkharitonov\.terraform\terraform.exe version
Terraform v0.12.20
C:\temp\terraform\cfg [master]>

Terraform Configuration Files

variable "codes" {
    default = ["abc"]
}

locals {
    codes = ["abc"]
    _y1 = [
        for code in var.codes: {
            for num in [1]: "${code}-${num}" => {
                code = code
                num = num
            }
        }
    ]
    x = merge(local._y1...)

    _y2 = flatten([for m in local._y1: [for k,v in m: { 
        key = k
        value = v
    }]])
#    x = zipmap(local._y2.*.key, local._y2.*.value)
}
output "x" {
    value = local.x
}

Expected Behavior

Should output this:

x = {
  "abc-1" = {
    "code" = "abc"
    "num" = 1
  }
}

Actual Behavior

Error: Invalid expanding argument value

  on main.tf line 15, in locals:
  15:     x = merge(local._y1...)

The expanding argument (indicated by ...) must be of a tuple, list, or set
type.

Steps to Reproduce

1. terraform init
2. terraform apply

Additional Context

If we replace var.codes with local.codes then it works.

To make it work with var.codes there is a workaround - comment out the first assignment to x and uncomment the second one which uses zipmap

References

https://stackoverflow.com/questions/60067168/terraform-is-unable-to-apply-the-operator

• Add issue_template #6017

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[bholzer]

I am encountering the same issue, but with a local

locals {
  # Define databases, and their roles with privileges
  databases = {
    for db in var.databases:
      db => {
        "${db}" = ["ALL"]
        "${db}_read" = ["CONNECT", "SELECT", "TEMP", "EXECUTE", "USAGE"] #readonly
      }
  }
}

resource "aws_secretsmanager_secret" "db_credentials" {
  for_each = keys(merge(values(local.databases)...))

  name = "RDSRole-${each.value}-${random_id.secret_id.hex}"
  rotation_lambda_arn = aws_lambda_function.rds_secret_rotator_lambda.arn

  rotation_rules {
    automatically_after_days = 30
  }
}

This code results in the same error:

In modules/database/main.tf line 206, in resource "aws_secretsmanager_secret" "db_credentials":
 206:   for_each = keys(merge(values(local.databases)...))

The expanding argument (indicated by ...) must be of a tuple, list, or set
type.

[UvaK]

This appears to be a duplicate of #22404 and it has a workaround for this issue.

[hashibot]

Hello! 🤖

This issue seems to be covering the same problem or request as #22404, so we're going to close it just to consolidate the discussion over there. Thanks!

[ghost]

I'm going to lock this issue because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active issues.

If you have found a problem that seems similar to this, please open a new issue and complete the issue template so we can capture all the details necessary to investigate further.