github.com/Ilhicas/nomad@v1.0.4-0.20210304152020-e86851182bc3/website/content/docs/job-specification/hcl2/functions/collection/element.mdx (about)

     1  ---
     2  layout: docs
     3  page_title: element - Functions - Configuration Language
     4  sidebar_title: element
     5  description: The element function retrieves a single element from a list.
     6  ---
     7  
     8  # `element` Function
     9  
    10  `element` retrieves a single element from a list.
    11  
    12  ```hcl
    13  element(list, index)
    14  ```
    15  
    16  The index is zero-based. This function produces an error if used with an
    17  empty list.
    18  
    19  Use the built-in index syntax `list[index]` in most cases. Use this function
    20  only for the special additional "wrap-around" behavior described below.
    21  
    22  ## Examples
    23  
    24  ```shell-session
    25  > element(["a", "b", "c"], 1)
    26  b
    27  ```
    28  
    29  If the given index is greater than the length of the list then the index is
    30  "wrapped around" by taking the index modulo the length of the list:
    31  
    32  ```shell-session
    33  > element(["a", "b", "c"], 3)
    34  a
    35  ```
    36  
    37  ## Related Functions
    38  
    39  - [`index`](/docs/job-specification/hcl2/functions/collection/index-fn) finds the index for a particular element value.
    40  - [`lookup`](/docs/job-specification/hcl2/functions/collection/lookup) retrieves a value from a _map_ given its _key_.