terraform/website/docs/configuration/functions/element.html.md

1.4 KiB

layout page_title sidebar_current description
language element - Functions - Configuration Language docs-funcs-collection-element The element function retrieves a single element from a list.

element Function

-> Note: This page is about Terraform 0.12 and later. For Terraform 0.11 and earlier, see 0.11 Configuration Language: Interpolation Syntax.

element retrieves a single element from a list.

element(list, index)

The index is zero-based. This function produces an error if used with an empty list. The index must be a non-negative integer.

Use the built-in index syntax list[index] in most cases. Use this function only for the special additional "wrap-around" behavior described below.

Examples

> element(["a", "b", "c"], 1)
b

If the given index is greater than the length of the list then the index is "wrapped around" by taking the index modulo the length of the list:

> element(["a", "b", "c"], 3)
a

To get the last element from the list use length to find the size of the list (minus 1 as the list is zero-based) and then pick the last element:

> element(["a", "b", "c"], length(["a", "b", "c"])-1)
c
  • index finds the index for a particular element value.
  • lookup retrieves a value from a map given its key.