3.9 KiB
title | description | categories | keywords | action | aliases | toc | ||||||||||||||
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range | Iterates over a non-empty collection, binds context (the dot) to successive elements, and executes the block. |
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true |
{{% include "functions/go-template/_common/truthy-falsy.md" %}}
{{ $s := slice "foo" "bar" "baz" }}
{{ range $var }}
{{ . }} → foo bar baz
{{ end }}
Use with the else
statement:
{{ $s := slice "foo" "bar" "baz" }}
{{ range $s }}
<p>{{ . }}</p>
{{ else }}
<p>The collection is empty</p>
{{ end }}
Within a range block:
- Use the
continue
statement to stop the innermost iteration and continue to the next iteration - Use the
break
statement to stop the innermost iteration and bypass all remaining iterations
Understanding context
At the top of a page template, the context (the dot) is a Page
object. Within the range
block, the context is bound to each successive element.
With this contrived example that uses the seq
function to generate a slice of integers:
{{ range seq 3 }}
{{ .Title }}
{{ end }}
Hugo will throw an error:
can't evaluate field Title in type int
The error occurs because we are trying to use the .Title
method on an integer instead of a Page
object. Within the range
block, if we want to render the page title, we need to get the context passed into the template.
{{% note %}}
Use the $
to get the context passed into the template.
{{% /note %}}
This template will render the page title three times:
{{ range seq 3 }}
{{ $.Title }}
{{ end }}
{{% note %}} Gaining a thorough understanding of context is critical for anyone writing template code. {{% /note %}}
Array or slice of scalars
This template code:
{{ $s := slice "foo" "bar" "baz" }}
{{ range $s }}
<p>{{ . }}</p>
{{ end }}
Is rendered to:
<p>foo</p>
<p>bar</p>
<p>baz</p>
This template code:
{{ $s := slice "foo" "bar" "baz" }}
{{ range $v := $s }}
<p>{{ $v }}</p>
{{ end }}
Is rendered to:
<p>foo</p>
<p>bar</p>
<p>baz</p>
This template code:
{{ $s := slice "foo" "bar" "baz" }}
{{ range $k, $v := $s }}
<p>{{ $k }}: {{ $v }}</p>
{{ end }}
Is rendered to:
<p>0: foo</p>
<p>1: bar</p>
<p>2: baz</p>
Array or slice of maps
This template code:
{{ $m := slice
(dict "name" "John" "age" 30)
(dict "name" "Will" "age" 28)
(dict "name" "Joey" "age" 24)
}}
{{ range $m }}
<p>{{ .name }} is {{ .age }}</p>
{{ end }}
Is rendered to:
<p>John is 30</p>
<p>Will is 28</p>
<p>Joey is 24</p>
Array or slice of pages
This template code:
{{ range where site.RegularPages "Type" "articles" }}
<h2><a href="{{ .RelPermalink }}">{{ .LinkTitle }}</a></h2>
{{ end }}
Is rendered to:
<h2><a href="/articles/article-3/">Article 3</a></h2>
<h2><a href="/articles/article-2/">Article 2</a></h2>
<h2><a href="/articles/article-1/">Article 1</a></h2>
Maps
This template code:
{{ $m := dict "name" "John" "age" 30 }}
{{ range $k, $v := $m }}
<p>key = {{ $k }} value = {{ $v }}</p>
{{ end }}
Is rendered to:
<p>key = age value = 30</p>
<p>key = name value = John</p>
Unlike ranging over an array or slice, Hugo sorts by key when ranging over a map.
{{% include "functions/go-template/_common/text-template.md" %}}