51 lines
1.2 KiB
Markdown
51 lines
1.2 KiB
Markdown
---
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layout: "language"
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page_title: "element - Functions - Configuration Language"
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sidebar_current: "docs-funcs-collection-element"
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description: |-
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The element function retrieves a single element from a list.
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---
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# `element` Function
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`element` retrieves a single element from a list.
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```hcl
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element(list, index)
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```
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The index is zero-based. This function produces an error if used with an
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empty list. The index must be a non-negative integer.
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Use the built-in index syntax `list[index]` in most cases. Use this function
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only for the special additional "wrap-around" behavior described below.
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## Examples
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```
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> element(["a", "b", "c"], 1)
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b
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```
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If the given index is greater than the length of the list then the index is
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"wrapped around" by taking the index modulo the length of the list:
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```
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> element(["a", "b", "c"], 3)
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a
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```
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To get the last element from the list use [`length`](./length.html) to find
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the size of the list (minus 1 as the list is zero-based) and then pick the
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last element:
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```
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> element(["a", "b", "c"], length(["a", "b", "c"])-1)
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c
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```
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## Related Functions
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* [`index`](./index_function.html) finds the index for a particular element value.
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* [`lookup`](./lookup.html) retrieves a value from a _map_ given its _key_.
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