packer-cn/website/pages/docs/from-1.5/functions/collection/length.mdx

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---
layout: docs
page_title: length - Functions - Configuration Language
sidebar_title: length
description: The length function determines the length of a collection or string.
---
# `length` Function
`length` determines the length of a given list, map, or string.
If given a list or map, the result is the number of elements in that collection.
If given a string, the result is the number of characters in the string.
## Examples
```shell-session
> length([])
0
> length(["a", "b"])
2
> length({"a" = "b"})
1
> length("hello")
5
```
When given a string, the result is the number of characters, rather than the
number of bytes or Unicode sequences that form them:
```shell-session
> length("👾🕹️")
2
```
A "character" is a _grapheme cluster_, as defined by
[Unicode Standard Annex #29](http://unicode.org/reports/tr29/). Note that
remote APIs may have a different definition of "character" for the purpose of
length limits on string arguments; a Packer provider is responsible for
translating Packer's string representation into that used by its respective
remote system and applying any additional validation rules to it.