--- title: Base Templates and Blocks linktitle: description: The base and block constructs allow you to define the outer shell of your master templates (i.e., the chrome of the page). godocref: https://golang.org/pkg/text/template/#example_Template_block date: 2017-02-01 publishdate: 2017-02-01 lastmod: 2017-02-01 categories: [templates,fundamentals] keywords: [blocks,base] menu: docs: parent: "templates" weight: 20 weight: 20 sections_weight: 20 draft: false aliases: [/templates/blocks/,/templates/base-templates-and-blocks/] toc: true --- The `block` keyword allows you to define the outer shell of your pages' one or more master template(s) and then fill in or override portions as necessary. {{< youtube QVOMCYitLEc >}} ## Base Template Lookup Order The [lookup order][lookup] for base templates is as follows: 1. `/layouts/section/-baseof.html` 2. `/themes//layouts/section/-baseof.html` 3. `/layouts//baseof.html` 4. `/themes//layouts//baseof.html` 5. `/layouts/section/baseof.html` 6. `/themes//layouts/section/baseof.html` 7. `/layouts/_default/-baseof.html` 8. `/themes//layouts/_default/-baseof.html` 9. `/layouts/_default/baseof.html` 10. `/themes//layouts/_default/baseof.html` Variables are denoted by capitalized text set within `<>`. Note that Hugo's default behavior is for `type` to inherit from `section` unless otherwise specified. ### Example Base Template Lookup Order As an example, let's assume your site is using a theme called "mytheme" when rendering the section list for a `post` section. Hugo picks `layout/section/post.html` as the template for [rendering the section][]. The `{{define}}` block in this template tells Hugo that the template is an extension of a base template. Here is the lookup order for the `post` base template: 1. `/layouts/section/post-baseof.html` 2. `/themes/mytheme/layouts/section/post-baseof.html` 3. `/layouts/post/baseof.html` 4. `/themes/mytheme/layouts/post/baseof.html` 5. `/layouts/section/baseof.html` 6. `/themes/mytheme/layouts/section/baseof.html` 7. `/layouts/_default/post-baseof.html` 8. `/themes/mytheme/layouts/_default/post-baseof.html` 9. `/layouts/_default/baseof.html` 10. `/themes/mytheme/layouts/_default/baseof.html` ## Define the Base Template The following defines a simple base template at `_default/baseof.html`. As a default template, it is the shell from which all your pages will be rendered unless you specify another `*baseof.html` closer to the beginning of the lookup order. {{< code file="layouts/_default/baseof.html" download="baseof.html" >}} {{ block "title" . }}  {{ .Site.Title }} {{ end }} {{ block "main" . }} {{ end }} {{ block "footer" . }} {{ end }} {{< /code >}} ## Override the Base Template From the above base template, you can define a [default list template][hugolists]. The default list template will inherit all of the code defined above and can then implement its own `"main"` block from: {{< code file="layouts/_default/list.html" download="list.html" >}} {{ define "main" }}

Posts

{{ end }} {{ end }} {{< /code >}} This replaces the contents of our (basically empty) "main" block with something useful for the list template. In this case, we didn't define a `"title"` block, so the contents from our base template remain unchanged in lists. {{% warning %}} Code that you put outside the block definitions *can* break your layout. This even includes HTML comments. For example: ``` {{ define "main" }} ...your code here {{ end }} ``` [See this thread from the Hugo discussion forums.](https://discourse.gohugo.io/t/baseof-html-block-templates-and-list-types-results-in-empty-pages/5612/6) {{% /warning %}} The following shows how you can override both the `"main"` and `"title"` block areas from the base template with code unique to your [default single page template][singletemplate]: {{< code file="layouts/_default/single.html" download="single.html" >}} {{ define "title" }} {{ .Title }} – {{ .Site.Title }} {{ end }} {{ define "main" }}

{{ .Content }} {{ end }} {{< /code >}} [hugolists]: /templates/lists [lookup]: /templates/lookup-order/ [rendering the section]: /templates/section-templates/ [singletemplate]: /templates/single-page-templates/