partials.md (7721B)
1 --- 2 title: Partial Templates 3 linktitle: Partial Templates 4 description: Partials are smaller, context-aware components in your list and page templates that can be used economically to keep your templating DRY. 5 date: 2017-02-01 6 publishdate: 2017-02-01 7 lastmod: 2017-02-01 8 categories: [templates] 9 keywords: [lists,sections,partials] 10 menu: 11 docs: 12 parent: "templates" 13 weight: 90 14 weight: 90 15 sections_weight: 90 16 draft: false 17 aliases: [/templates/partial/,/layout/chrome/,/extras/analytics/] 18 toc: true 19 --- 20 21 {{< youtube pjS4pOLyB7c >}} 22 23 ## Partial Template Lookup Order 24 25 Partial templates---like [single page templates][singletemps] and [list page templates][listtemps]---have a specific [lookup order][]. However, partials are simpler in that Hugo will only check in two places: 26 27 1. `layouts/partials/*<PARTIALNAME>.html` 28 2. `themes/<THEME>/layouts/partials/*<PARTIALNAME>.html` 29 30 This allows a theme's end user to copy a partial's contents into a file of the same name for [further customization][customize]. 31 32 ## Use Partials in your Templates 33 34 All partials for your Hugo project are located in a single `layouts/partials` directory. For better organization, you can create multiple subdirectories within `partials` as well: 35 36 ```txt 37 layouts/ 38 └── partials/ 39 ├── footer/ 40 │ ├── scripts.html 41 │ └── site-footer.html 42 ├── head/ 43 │ ├── favicons.html 44 │ ├── metadata.html 45 │ ├── prerender.html 46 │ └── twitter.html 47 └── header/ 48 ├── site-header.html 49 └── site-nav.html 50 ``` 51 52 All partials are called within your templates using the following pattern: 53 54 ```go-html-template 55 {{ partial "<PATH>/<PARTIAL>.html" . }} 56 ``` 57 58 {{% note %}} 59 One of the most common mistakes with new Hugo users is failing to pass a context to the partial call. In the pattern above, note how "the dot" (`.`) is required as the second argument to give the partial context. You can read more about "the dot" in the [Hugo templating introduction](/templates/introduction/). 60 {{% /note %}} 61 62 {{% note %}} 63 `<PARTIAL>` including `baseof` is reserved. ([#5373](https://github.com/gohugoio/hugo/issues/5373)) 64 {{% /note %}} 65 66 As shown in the above example directory structure, you can nest your directories within `partials` for better source organization. You only need to call the nested partial's path relative to the `partials` directory: 67 68 ```go-html-template 69 {{ partial "header/site-header.html" . }} 70 {{ partial "footer/scripts.html" . }} 71 ``` 72 73 ### Variable Scoping 74 75 The second argument in a partial call is the variable being passed down. The above examples are passing the `.`, which tells the template receiving the partial to apply the current [context][context]. 76 77 This means the partial will *only* be able to access those variables. The partial is isolated and *has no access to the outer scope*. From within the partial, `$.Var` is equivalent to `.Var`. 78 79 ## Returning a value from a Partial 80 81 In addition to outputting markup, partials can be used to return a value of any type. In order to return a value, a partial must include a lone `return` statement _at the end of the partial_. 82 83 ### Example GetFeatured 84 85 ```go-html-template 86 {{/* layouts/partials/GetFeatured.html */}} 87 {{ return first . (where site.RegularPages "Params.featured" true) }} 88 ``` 89 90 ```go-html-template 91 {{/* layouts/index.html */}} 92 {{ range partial "GetFeatured.html" 5 }} 93 [...] 94 {{ end }} 95 ``` 96 97 ### Example GetImage 98 99 ```go-html-template 100 {{/* layouts/partials/GetImage.html */}} 101 {{ $image := false }} 102 {{ with .Params.gallery }} 103 {{ $image = index . 0 }} 104 {{ end }} 105 {{ with .Params.image }} 106 {{ $image = . }} 107 {{ end }} 108 {{ return $image }} 109 ``` 110 111 ```go-html-template 112 {{/* layouts/_default/single.html */}} 113 {{ with partial "GetImage.html" . }} 114 [...] 115 {{ end }} 116 ``` 117 118 {{% note %}} 119 Only one `return` statement is allowed per partial file. 120 {{% /note %}} 121 122 ## Inline Partials 123 124 {{< new-in "0.74.0" >}} 125 126 You can also define partials inline in the template. But remember that template namespace is global, so you need to make sure that the names are unique to avoid conflicts. 127 128 ```go-html-template 129 Value: {{ partial "my-inline-partial.html" . }} 130 131 {{ define "partials/my-inline-partial.html" }} 132 {{ $value := 32 }} 133 {{ return $value }} 134 {{ end }} 135 ``` 136 137 ## Cached Partials 138 139 The [`partialCached` template function][partialcached] can offer significant performance gains for complex templates that don't need to be re-rendered on every invocation. The simplest usage is as follows: 140 141 ```go-html-template 142 {{ partialCached "footer.html" . }} 143 ``` 144 145 You can also pass additional parameters to `partialCached` to create *variants* of the cached partial. 146 147 For example, you can tell Hugo to only render the partial `footer.html` once per section: 148 149 ```go-html-template 150 {{ partialCached "footer.html" . .Section }} 151 ``` 152 153 If you need to pass additional parameters to create unique variants, you can pass as many variant parameters as you need: 154 155 ```go-html-template 156 {{ partialCached "footer.html" . .Params.country .Params.province }} 157 ``` 158 159 Note that the variant parameters are not made available to the underlying partial template. They are only use to create a unique cache key. 160 161 ### Example `header.html` 162 163 The following `header.html` partial template is used for [spf13.com](https://spf13.com/): 164 165 {{< code file="layouts/partials/header.html" download="header.html" >}} 166 <!DOCTYPE html> 167 <html class="no-js" lang="en-US" prefix="og: http://ogp.me/ns# fb: http://ogp.me/ns/fb#"> 168 <head> 169 <meta charset="utf-8"> 170 171 {{ partial "meta.html" . }} 172 173 <base href="{{ .Site.BaseURL }}"> 174 <title> {{ .Title }} : spf13.com </title> 175 <link rel="canonical" href="{{ .Permalink }}"> 176 {{ if .RSSLink }}<link href="{{ .RSSLink }}" rel="alternate" type="application/rss+xml" title="{{ .Title }}" />{{ end }} 177 178 {{ partial "head_includes.html" . }} 179 </head> 180 {{< /code >}} 181 182 {{% note %}} 183 The `header.html` example partial was built before the introduction of block templates to Hugo. Read more on [base templates and blocks](/templates/base/) for defining the outer chrome or shell of your master templates (i.e., your site's head, header, and footer). You can even combine blocks and partials for added flexibility. 184 {{% /note %}} 185 186 ### Example `footer.html` 187 188 The following `footer.html` partial template is used for [spf13.com](https://spf13.com/): 189 190 {{< code file="layouts/partials/footer.html" download="footer.html" >}} 191 <footer> 192 <div> 193 <p> 194 © 2013-14 Steve Francia. 195 <a href="https://creativecommons.org/licenses/by/3.0/" title="Creative Commons Attribution">Some rights reserved</a>; 196 please attribute properly and link back. 197 </p> 198 </div> 199 </footer> 200 {{< /code >}} 201 202 [context]: /templates/introduction/ "The most easily overlooked concept to understand about Go templating is how the dot always refers to the current context." 203 [customize]: /themes/customizing/ "Hugo provides easy means to customize themes as long as users are familiar with Hugo's template lookup order." 204 [listtemps]: /templates/lists/ "To effectively leverage Hugo's system, see how Hugo handles list pages, where content for sections, taxonomies, and the homepage are listed and ordered." 205 [lookup order]: /templates/lookup-order/ "To keep your templating dry, read the documentation on Hugo's lookup order." 206 [partialcached]: /functions/partialcached/ "Use the partial cached function to improve build times in cases where Hugo can cache partials that don't need to be rendered with every page." 207 [singletemps]: /templates/single-page-templates/ "The most common form of template in Hugo is the single content template. Read the docs on how to create templates for individual pages." 208 [themes]: /themes/