hugo/content/en/variables/page.md
Bjørn Erik Pedersen 3a44bf182f Squashed 'docs/' changes from 81847981f..d88477eb3
d88477eb3 Fix some more redirect alias loops
209735670 Update features.md
d4ec6ef87 Remove redirect loop from functions/default
ce14da435 Fix the AlternativeOutputFormats/OutputFormats examples
f64a22469 Update cond.md
357a70a32 Remove redirect loop from templates/404
4ad7b01ba Remove some aliases that were causing infinite redirect loops
fd378e66a Fix alias redirect loop
ec3629f6f Revert "Set code background to white"
ffc56b880 Revert "Make inline code gray"
2a964e261 Make inline code gray
44069e09c Set code background to white
d39c790d0 Linked my own blog2md migration script
3e55267be Release 0.46
7b6cfdd8b releaser: Prepare repository for 0.47-DEV
d4cb54806 releaser: Add release notes to /docs for release of 0.46
6518ac7e7 releaser: Bump versions for release of 0.46
e54334d5c Merge commit '766085c2dc6fc95ac30fda2a9ebde2355fc12554'

git-subtree-dir: docs
git-subtree-split: d88477eb3a1959e2764d6025f5aa7a57a4a611e7
2018-08-08 13:54:28 +02:00

296 lines
10 KiB
Markdown

---
title: Page Variables
linktitle:
description: Page-level variables are defined in a content file's front matter, derived from the content's file location, or extracted from the content body itself.
date: 2017-02-01
publishdate: 2017-02-01
lastmod: 2017-02-01
categories: [variables and params]
keywords: [pages]
draft: false
menu:
docs:
title: "variables defined by a page"
parent: "variables"
weight: 20
weight: 20
sections_weight: 20
aliases: []
toc: true
---
The following is a list of page-level variables. Many of these will be defined in the front matter, derived from file location, or extracted from the content itself.
{{% note "`.Scratch`" %}}
See [`.Scratch`](/functions/scratch/) for page-scoped, writable variables.
{{% /note %}}
## Page Variables
.AlternativeOutputFormats
: contains all alternative formats for a given page; this variable is especially useful `link rel` list in your site's `<head>`. (See [Output Formats](/templates/output-formats/).)
.Content
: the content itself, defined below the front matter.
.Data
: the data specific to this type of page.
.Date
: the date associated with the page; `.Date` pulls from the `date` field in a content's front matter. See also `.ExpiryDate`, `.PublishDate`, and `.Lastmod`.
.Description
: the description for the page.
.Dir
: the path of the folder containing this content file. The path is relative to the `content` folder.
.Draft
: a boolean, `true` if the content is marked as a draft in the front matter.
.ExpiryDate
: the date on which the content is scheduled to expire; `.ExpiryDate` pulls from the `expirydate` field in a content's front matter. See also `.PublishDate`, `.Date`, and `.Lastmod`.
.File
: filesystem-related data for this content file. See also [File Variables][].
.FuzzyWordCount
: the approximate number of words in the content.
.Hugo
: see [Hugo Variables](/variables/hugo/).
.IsHome
: `true` in the context of the [homepage](/templates/homepage/).
.IsNode
: always `false` for regular content pages.
.IsPage
: always `true` for regular content pages.
.IsTranslated
: `true` if there are translations to display.
.Keywords
: the meta keywords for the content.
.Kind
: the page's *kind*. Possible return values are `page`, `home`, `section`, `taxonomy`, or `taxonomyTerm`. Note that there are also `RSS`, `sitemap`, `robotsTXT`, and `404` kinds, but these are only available during the rendering of each of these respective page's kind and therefore *not* available in any of the `Pages` collections.
.Lang
: language taken from the language extension notation.
.Language
: a language object that points to the language's definition in the site
`config`.
.Lastmod
: the date the content was last modified. `.Lastmod` pulls from the `lastmod` field in a content's front matter.
- If `lastmod` is not set, and `.GitInfo` feature is disabled, the front matter `date` field will be used.
- If `lastmod` is not set, and `.GitInfo` feature is enabled, `.GitInfo.AuthorDate` will be used instead.
See also `.ExpiryDate`, `.Date`, `.PublishDate`, and [`.GitInfo`][gitinfo].
.LinkTitle
: access when creating links to the content. If set, Hugo will use the `linktitle` from the front matter before `title`.
.Next
: pointer to the following content (based on the `publishdate` field in front matter).
.NextInSection
: pointer to the following content within the same section (based on `publishdate` field in front matter).
.OutputFormats
: contains all formats, including the current format, for a given page. Can be combined the with [`.Get` function](/functions/get/) to grab a specific format. (See [Output Formats](/templates/output-formats/).)
.Pages
: a collection of associated pages. This value will be `nil` within
the context of regular content pages. See [`.Pages`](#pages).
.Permalink
: the Permanent link for this page; see [Permalinks](/content-management/urls/)
.Plain
: the Page content stripped of HTML tags and presented as a string.
.PlainWords
: the Page content stripped of HTML as a `[]string` using Go's [`strings.Fields`](https://golang.org/pkg/strings/#Fields) to split `.Plain` into a slice.
.Prev
: Pointer to the previous content (based on `publishdate` in front matter).
.PrevInSection
: Pointer to the previous content within the same section (based on `publishdate` in front matter). For example, `{{if .PrevInSection}}{{.PrevInSection.Permalink}}{{end}}`.
.PublishDate
: the date on which the content was or will be published; `.Publishdate` pulls from the `publishdate` field in a content's front matter. See also `.ExpiryDate`, `.Date`, and `.Lastmod`.
.RSSLink
: link to the taxonomies' RSS link.
.RawContent
: raw markdown content without the front matter. Useful with [remarkjs.com](
http://remarkjs.com)
.ReadingTime
: the estimated time, in minutes, it takes to read the content.
.Ref
: returns the permalink for a given reference (e.g., `.Ref "sample.md"`). `.Ref` does *not* handle in-page fragments correctly. See [Cross References](/content-management/cross-references/).
.RelPermalink
: the relative permanent link for this page.
.RelRef
: returns the relative permalink for a given reference (e.g., `RelRef
"sample.md"`). `.RelRef` does *not* handle in-page fragments correctly. See [Cross References](/content-management/cross-references/).
.Site
: see [Site Variables](/variables/site/).
.Summary
: a generated summary of the content for easily showing a snippet in a summary view. The breakpoint can be set manually by inserting <code>&lt;!&#x2d;&#x2d;more&#x2d;&#x2d;&gt;</code> at the appropriate place in the content page. See [Content Summaries](/content-management/summaries/) for more details.
.TableOfContents
: the rendered [table of contents](/content-management/toc/) for the page.
.Title
: the title for this page.
.Translations
: a list of translated versions of the current page. See [Multilingual Mode](/content-management/multilingual/) for more information.
.Truncated
: a boolean, `true` if the `.Summary` is truncated. Useful for showing a "Read more..." link only when necessary. See [Summaries](/content-management/summaries/) for more information.
.Type
: the [content type](/content-management/types/) of the content (e.g., `post`).
.URL
: the URL for the page relative to the web root. Note that a `url` set directly in front matter overrides the default relative URL for the rendered page.
.UniqueID
: the MD5-checksum of the content file's path.
.Weight
: assigned weight (in the front matter) to this content, used in sorting.
.WordCount
: the number of words in the content.
## Section Variables and Methods
Also see [Sections](/content-management/sections/).
{{< readfile file="/content/en/readfiles/sectionvars.md" markdown="true" >}}
## The `.Pages` Variable {#pages}
`.Pages` is an alias to `.Data.Pages`. It is conventional to use the
aliased form `.Pages`.
### `.Pages` compared to `.Site.Pages`
{{< readfile file="/content/en/readfiles/pages-vs-site-pages.md" markdown="true" >}}
## Page-level Params
Any other value defined in the front matter in a content file, including taxonomies, will be made available as part of the `.Params` variable.
```
---
title: My First Post
date: 2017-02-20T15:26:23-06:00
categories: [one]
tags: [two,three,four]
```
With the above front matter, the `tags` and `categories` taxonomies are accessible via the following:
* `.Params.tags`
* `.Params.categories`
{{% note "Casing of Params" %}}
Page-level `.Params` are *only* accessible in lowercase.
{{% /note %}}
The `.Params` variable is particularly useful for the introduction of user-defined front matter fields in content files. For example, a Hugo website on book reviews could have the following front matter in `/content/review/book01.md`:
```
---
...
affiliatelink: "http://www.my-book-link.here"
recommendedby: "My Mother"
...
---
```
These fields would then be accessible to the `/themes/yourtheme/layouts/review/single.html` template through `.Params.affiliatelink` and `.Params.recommendedby`, respectively.
Two common situations where this type of front matter field could be introduced is as a value of a certain attribute like `href=""` or by itself to be displayed as text to the website's visitors.
{{< code file="/themes/yourtheme/layouts/review/single.html" >}}
<h3><a href={{ printf "%s" $.Params.affiliatelink }}>Buy this book</a></h3>
<p>It was recommended by {{ .Params.recommendedby }}.</p>
{{< /code >}}
This template would render as follows, assuming you've set [`uglyURLs`](/content-management/urls/) to `false` in your [site `config`](/getting-started/configuration/):
{{< output file="yourbaseurl/review/book01/index.html" >}}
<h3><a href="http://www.my-book-link.here">Buy this book</a></h3>
<p>It was recommended by my Mother.</p>
{{< /output >}}
{{% note %}}
See [Archetypes](/content-management/archetypes/) for consistency of `Params` across pieces of content.
{{% /note %}}
### The `.Param` Method
In Hugo, you can declare params in individual pages and globally for your entire website. A common use case is to have a general value for the site param and a more specific value for some of the pages (i.e., a header image):
```
{{ $.Param "header_image" }}
```
The `.Param` method provides a way to resolve a single value according to it's definition in a page parameter (i.e. in the content's front matter) or a site parameter (i.e., in your `config`).
### Access Nested Fields in Front Matter
When front matter contains nested fields like the following:
```
---
author:
given_name: John
family_name: Feminella
display_name: John Feminella
---
```
`.Param` can access these fields by concatenating the field names together with a dot:
```
{{ $.Param "author.display_name" }}
```
If your front matter contains a top-level key that is ambiguous with a nested key, as in the following case:
```
---
favorites.flavor: vanilla
favorites:
flavor: chocolate
---
```
The top-level key will be preferred. Therefore, the following method, when applied to the previous example, will print `vanilla` and not `chocolate`:
```
{{ $.Param "favorites.flavor" }}
=> vanilla
```
[gitinfo]: /variables/git/
[File Variables]: /variables/files/