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hugo/docs/content/en/functions/collections/NewScratch.md

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---
title: collections.NewScratch
description: Returns a locally scoped "scratch pad" to store and manipulate data.
categories: []
keywords: []
action:
aliases: [newScratch]
related:
- methods/page/scratch
- methods/page/store
- methods/shortcode/scratch
returnType: maps.Scratch
signatures: [collections.NewScratch ]
---
The `collections.NewScratch` function creates a locally scoped [scratch pad] to store and manipulate data. To create a scratch pad that is attached to a `Page` object, use the [`Scratch`] or [`Store`] method.
[`Scratch`]: /methods/page/scratch/
[`Store`]: /methods/page/store/
[scratch pad]: /getting-started/glossary/#scratch-pad
## Methods
###### Set
Sets the value of a given key.
```go-html-template
{{ $s := newScratch }}
{{ $s.Set "greeting" "Hello" }}
```
###### Get
Gets the value of a given key.
```go-html-template
{{ $s := newScratch }}
{{ $s.Set "greeting" "Hello" }}
{{ $s.Get "greeting" }} → Hello
```
###### Add
Adds a given value to existing value(s) of the given key.
For single values, `Add` accepts values that support Go's `+` operator. If the first `Add` for a key is an array or slice, the following adds will be appended to that list.
```go-html-template
{{ $s := newScratch }}
{{ $s.Set "greeting" "Hello" }}
{{ $s.Add "greeting" "Welcome" }}
{{ $s.Get "greeting" }} → HelloWelcome
```
```go-html-template
{{ $s := newScratch }}
{{ $s.Set "total" 3 }}
{{ $s.Add "total" 7 }}
{{ $s.Get "total" }} → 10
```
```go-html-template
{{ $s := newScratch }}
{{ $s.Set "greetings" (slice "Hello") }}
{{ $s.Add "greetings" (slice "Welcome" "Cheers") }}
{{ $s.Get "greetings" }} → [Hello Welcome Cheers]
```
###### SetInMap
Takes a `key`, `mapKey` and `value` and adds a map of `mapKey` and `value` to the given `key`.
```go-html-template
{{ $s := newScratch }}
{{ $s.SetInMap "greetings" "english" "Hello" }}
{{ $s.SetInMap "greetings" "french" "Bonjour" }}
{{ $s.Get "greetings" }} → map[english:Hello french:Bonjour]
```
###### DeleteInMap
Takes a `key` and `mapKey` and removes the map of `mapKey` from the given `key`.
```go-html-template
{{ $s := newScratch }}
{{ $s.SetInMap "greetings" "english" "Hello" }}
{{ $s.SetInMap "greetings" "french" "Bonjour" }}
{{ $s.DeleteInMap "greetings" "english" }}
{{ $s.Get "greetings" }} → map[french:Bonjour]
```
###### GetSortedMapValues
Returns an array of values from `key` sorted by `mapKey`.
```go-html-template
{{ $s := newScratch }}
{{ $s.SetInMap "greetings" "english" "Hello" }}
{{ $s.SetInMap "greetings" "french" "Bonjour" }}
{{ $s.GetSortedMapValues "greetings" }} → [Hello Bonjour]
```
###### Delete
Removes the given key.
```go-html-template
{{ $s := newScratch }}
{{ $s.Set "greeting" "Hello" }}
{{ $s.Delete "greeting" }}
```
###### Values
Returns the raw backing map. Do not use with `Scratch` or `Store` methods on a `Page` object due to concurrency issues.
```go-html-template
{{ $s := newScratch }}
{{ $s.SetInMap "greetings" "english" "Hello" }}
{{ $s.SetInMap "greetings" "french" "Bonjour" }}
{{ $map := $s.Values }}
```