hugo/docs/content/en/functions/default.md
2023-05-22 16:47:07 +02:00

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---
title: default
description: Allows setting a default value that can be returned if a first value is not set.
qref: "Returns a default value if a value is not set when checked."
keywords: [defaults]
categories: [functions]
menu:
docs:
parent: functions
toc:
signature: ["default DEFAULT INPUT"]
relatedfuncs: []
---
`default` checks whether a given value is set and returns a default value if it is not. *Set* in this context means different things depending on the data type:
* non-zero for numeric types and times
* non-zero length for strings, arrays, slices, and maps
* any boolean or struct value
* non-nil for any other types
`default` function examples reference the following content page:
{{< code file="content/posts/default-function-example.md" >}}
---
title: Sane Defaults
seo_title:
date: 2017-02-18
font:
oldparam: The default function helps make your templating DRYer.
newparam:
---
{{< /code >}}
`default` can be written in more than one way:
```go-html-template
{{ .Params.font | default "Roboto" }}
{{ default "Roboto" .Params.font }}
```
Both of the above `default` function calls return `Roboto`.
A `default` value, however, does not need to be hard coded like the previous example. The `default` value can be a variable or pulled directly from the front matter using dot notation:
```go-html-template
{{ $old := .Params.oldparam }}
<p>{{ .Params.newparam | default $old }}</p>
```
Which would return:
```html
<p>The default function helps make your templating DRYer.</p>
```
And then using dot notation
```go-html-template
<title>{{ .Params.seo_title | default .Title }}</title>
```
Which would return
```html
<title>Sane Defaults</title>
```
The following have equivalent return values but are far less terse. This demonstrates the utility of `default`:
Using `if`:
```go-html-template
<title>{{ if .Params.seo_title }}{{ .Params.seo_title }}{{ else }}{{ .Title }}{{ end }}</title>
=> Sane Defaults
```
Using `with`:
```go-html-template
<title>{{ with .Params.seo_title }}{{ . }}{{ else }}{{ .Title }}{{ end }}</title>
=> Sane Defaults
```