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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."
date: 2017-02-01
publishdate: 2017-02-01
lastmod: 2017-02-01
keywords: [defaults]
categories: [functions]
menu:
docs:
parent: "functions"
toc:
signature: ["default DEFAULT INPUT"]
workson: []
hugoversion:
relatedfuncs: []
deprecated: false
draft: false
aliases: []
---
`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:
```
{{ index .Params "font" | default "Roboto" }}
{{ default "Roboto" (index .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:
{{< code file="variable-as-default-value.html" nocopy="true" >}}
{{$old := .Params.oldparam }}
<p>{{ .Params.newparam | default $old }}</p>
{{< /code >}}
Which would return:
```
<p>The default function helps make your templating DRYer.</p>
```
And then using dot notation
{{< code file="dot-notation-default-value.html" >}}
<title>{{ .Params.seo_title | default .Title }}</title>
{{< /code >}}
Which would return
{{< output file="dot-notation-default-return-value.html" >}}
<title>Sane Defaults</title>
{{< /output >}}
The following have equivalent return values but are far less terse. This demonstrates the utility of `default`:
Using `if`:
{{< code file="if-instead-of-default.html" nocopy="true" >}}
<title>{{if .Params.seo_title}}{{.Params.seo_title}}{{else}}{{.Title}}{{end}}</title>
=> Sane Defaults
{{< /code >}}
Using `with`:
{{< code file="with-instead-of-default.html" nocopy="true" >}}
<title>{{with .Params.seo_title}}{{.}}{{else}}{{.Title}}{{end}}</title>
=> Sane Defaults
{{< /code >}}
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