> ## Documentation Index
> Fetch the complete documentation index at: https://notes.kodekloud.com/llms.txt
> Use this file to discover all available pages before exploring further.
# for each
> This article explores using the for_each meta-argument in Terraform to manage resources more reliably than with the count meta-argument.
In this lesson, we explore the powerful for\_each meta-argument in Terraform. By using for\_each, you can overcome some limitations of the count meta-argument and manage resources more reliably.
## Using count with a List
Traditionally, resources are created using the count meta-argument. For example:
```hcl theme={null}
resource "local_file" "pet" {
filename = var.filename[count.index]
count = length(var.filename)
}
```
```hcl theme={null}
variable "filename" {
default = [
"/root/pets.txt",
"/root/dogs.txt",
"/root/cats.txt"
]
}
```
This configuration creates resources as a list. However, updating resources based on index positions can lead to unexpected behavior when the list order changes.
## Transitioning to for\_each
Switching to for\_each can help manage resources more effectively by assigning a unique key to each resource using each.value. An initial attempt might be:
```hcl theme={null}
resource "local_file" "pet" {
filename = var.filename[count.index]
for_each = var.filename
}
variable "filename" {
default = [
"/root/pets.txt",
"/root/dogs.txt",
"/root/cats.txt"
]
}
```
Running `terraform plan` with this configuration results in an error. The for\_each argument only supports a map or a set of strings – not a list of strings. The error message appears similar to:
```bash theme={null}
$ terraform plan
Error: Invalid for_each argument
on main.tf line 2, in resource "local_file" "pet":
2: for_each = var.filename
The given "for_each" argument value is unsuitable: the "for_each"
argument must be a map, or set of strings, and you have provided a value
of type list of string.
```
Ensure that the data type passed to for\_each complies with Terraform's requirements—a map or a set of strings.
### Correcting the Configuration
There are two approaches to resolve this issue:
1. Change the variable type from a list to a set (sets do not allow duplicate elements).
2. Convert the list into a set in the resource block using Terraform's built-in `toset` function.
Below is an updated configuration that uses the `toset` function:
```hcl theme={null}
resource "local_file" "pet" {
filename = each.value
for_each = toset(var.filename)
}
variable "filename" {
type = list(string)
default = [
"/root/pets.txt",
"/root/dogs.txt",
"/root/cats.txt"
]
}
```
When you run `terraform plan` now, Terraform will indicate that three resources will be created:
```bash theme={null}
$ terraform plan
Terraform will perform the following actions:
# local_file.pet["/root/cats.txt"] will be created
+ resource "local_file" "pet" {
+ directory_permission = "0777"
+ file_permission = "0777"
+ filename = "/root/cats.txt"
}
...