hugo/docs/content/en/functions/default.md

title	description	qref	date	publishdate	lastmod	keywords	categories	menu	toc	signature	workson	hugoversion	relatedfuncs	deprecated	draft	aliases
default	Allows setting a default value that can be returned if a first value is not set.	Returns a default value if a value is not set when checked.	2017-02-01	2017-02-01	2017-02-01	defaults	functions	docs parent functions		default DEFAULT INPUT				false	false

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 }}

{{ .Params.newparam | default $old }}

{{< /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" >}}

{{< /code >}}

Which would return

{{< output file="dot-notation-default-return-value.html" >}}

{{< /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" >}}

=> Sane Defaults {{< /code >}}

Using with:

{{< code file="with-instead-of-default.html" nocopy="true" >}}

=> Sane Defaults {{< /code >}}