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---
title: IsDescendant
description: Reports whether PAGE1 in a descendant of PAGE2.
categories: []
keywords: []
action:
related:
- methods/page/Ancestors
- methods/page/CurrentSection
- methods/page/FirstSection
- methods/page/InSection
- methods/page/IsAncestor
- methods/page/Parent
- methods/page/Sections
returnType: bool
signatures: [PAGE1.IsDescendant PAGE2]
---
{{% include "methods/page/_common/definition-of-section.md" %}}
With this content structure:
```text
content/
├── auctions/
│ ├── 2023-11/
│ │ ├── _index.md
│ │ ├── auction-1.md
│ │ └── auction-2.md
│ ├── 2023-12/
│ │ ├── _index.md
│ │ ├── auction-3.md
│ │ └── auction-4.md
│ ├── _index.md
│ ├── bidding.md
│ └── payment.md
└── _index.md
```
When rendering the "auctions" page:
```go-html-template
{{ with .Site.GetPage "/" }}
{{ $.IsDescendant . }} → true
{{ end }}
{{ with .Site.GetPage "/auctions" }}
{{ $.IsDescendant . }} → false
{{ end }}
{{ with .Site.GetPage "/auctions/2023-11" }}
{{ $.IsDescendant . }} → false
{{ end }}
{{ with .Site.GetPage "/auctions/2023-11/auction-2" }}
{{ $.IsDescendant . }} → false
{{ end }}
```
In the examples above we are coding defensively using the [`with`] statement, returning nothing if the page does not exist. By adding an [`else`] clause we can do some error reporting:
```go-html-template
{{ $path := "/auctions/2023-11" }}
{{ with .Site.GetPage $path }}
{{ $.IsDescendant . }} → true
{{ else }}
{{ errorf "Unable to find the section with path %s" $path }}
{{ end }}
```
## Understanding context
Inside of the `with` block, the [context] (the dot) is the section `Page` object, not the `Page` object passed into the template. If we were to use this syntax:
```go-html-template
{{ with .Site.GetPage "/auctions" }}
{{ .IsDescendant . }} → true
{{ end }}
```
The result would be wrong when rendering the "auction-1" page because we are comparing the section page to itself.
{{% note %}}
Use the `$` to get the context passed into the template.
{{% /note %}}
```go-html-template
{{ with .Site.GetPage "/auctions" }}
{{ $.IsDescendant . }} → true
{{ end }}
```
{{% note %}}
Gaining a thorough understanding of context is critical for anyone writing template code.
{{% /note %}}
[context]: /getting-started/glossary/#context
[`with`]: /functions/go-template/with
[`else`]: /functions/go-template/else
|
