mirror of
https://github.com/gohugoio/hugo.git
synced 2024-11-14 20:37:55 -05:00
ba45da9d03
32356e4e Fix typo in header of shortcode-templates.md c8f1a2d2 Correct code example for index template function bfa6a55d Escape code fencing ff8b2f99 Fix typos in deployment with wercker tutorial 557c36e8 theme: Merge commit '7fbb4bed25001182bfeb91f79db0f0c1936582ee' 7fbb4bed Squashed 'themes/gohugoioTheme/' changes from 7dd8a302..ca53082d ce31cee0 Add "See Also" config 158cee1b Make the tags into keywords 61600be6 Add a note to the related section 49edb5a2 Relase 0.27.1 c9bbc001 releaser: Add release notes to /docs for release of 0.27.1 213c6c3b Add bugs poster 8b4590cd Add KeyCDN integration tutorial 2b277859 Add tutorial videos to several docs pages 950fef1f Update roadmap to link to the correct milestones page 496f5bf6 Rename relnotes d6f9378d Bump Netlify versions to 0.27 087fde7f Update 0.27 release notes 603f94ae docs: Document Related Content 3790f6a3 releaser: Bump versions for release of 0.27 0948868c releaser: Add release notes to /docs for release of 0.27 git-subtree-dir: docs git-subtree-split: 32356e4eabe357ae914f4d1d59e8ae31ce936723
60 lines
No EOL
2 KiB
Markdown
60 lines
No EOL
2 KiB
Markdown
---
|
|
title: len
|
|
linktitle: len
|
|
description: Returns the length of a variable according to its type.
|
|
godocref: https://golang.org/pkg/builtin/#len
|
|
date: 2017-02-01
|
|
publishdate: 2017-02-01
|
|
lastmod: 2017-04-18
|
|
categories: [functions]
|
|
keywords: []
|
|
signature: ["len INPUT"]
|
|
workson: [lists,taxonomies,terms]
|
|
hugoversion:
|
|
relatedfuncs: []
|
|
deprecated: false
|
|
toc: false
|
|
aliases: []
|
|
---
|
|
|
|
`len` is a built-in function in Golang that returns the length of a variable according to its type. From the Golang documentation:
|
|
|
|
> Array: the number of elements in v.
|
|
>
|
|
> Pointer to array: the number of elements in *v (even if v is nil).
|
|
>
|
|
> Slice, or map: the number of elements in v; if v is nil, len(v) is zero.
|
|
>
|
|
> String: the number of bytes in v.
|
|
>
|
|
> Channel: the number of elements queued (unread) in the channel buffer; if v is nil, len(v) is zero.
|
|
|
|
`len` is also considered a [fundamental function for Hugo templating][].
|
|
|
|
## `len` Example 1: Longer Headings
|
|
|
|
You may want to append a class to a heading according to the length of the string therein. The following templating checks to see if the title's length is greater than 80 characters and, if so, adds a `long-title` class to the `<h1>`:
|
|
|
|
{{< code file="check-title-length.html" >}}
|
|
<header>
|
|
<h1{{if gt (len .Title) 80}} class="long-title"{{end}}>{{.Title}}</h1>
|
|
</header>
|
|
{{< /code >}}
|
|
|
|
## `len` Example 2: Counting Pages with `where`
|
|
|
|
The following templating uses [`where`][] in conjunction with `len` to figure out the total number of content pages in a `posts` [section][]:
|
|
|
|
{{< code file="how-many-posts.html" >}}
|
|
{{ $posts := (where .Site.RegularPages "Section" "==" "post") }}
|
|
{{ $postCount := len $posts }}
|
|
{{< /code >}}
|
|
|
|
Note the use of `.RegularPages`, a [site variable][] that counts all regular content pages but not the `_index.md` pages used to add front matter and content to [list templates][].
|
|
|
|
|
|
[fundamental function for Hugo templating]: /templates/introduction/
|
|
[list templates]: /templates/lists/
|
|
[section]: /content-management/sections/
|
|
[site variable]: /variables/site/
|
|
[`where`]: /functions/where/ |