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---
title: merge
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description: "Returns the result of merging two or more maps."
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date: 2019-08-08
categories: [functions]
menu:
docs:
parent: "functions"
keywords: [dictionary]
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signature: ["collections.Merge MAP MAP...", "merge MAP MAP..."]
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workson: []
hugoversion: "0.56.0"
relatedfuncs: [dict, append, reflect.IsMap, reflect.IsSlice]
aliases: []
---
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Returns the result of merging two or more maps from left to right. If a key already exists, `merge` updates its value. If a key is absent, `merge` inserts the value under the new key.
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Key handling is case-insensitive.
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The following examples use these map definitions:
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```go-html-template
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{{ $m1 := dict "x" "foo" }}
{{ $m2 := dict "x" "bar" "y" "wibble" }}
{{ $m3 := dict "x" "baz" "y" "wobble" "z" (dict "a" "huey") }}
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```
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Example 1
```go-html-template
{{ $merged := merge $m1 $m2 $m3 }}
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{{ $merged.x }} --> baz
{{ $merged.y }} --> wobble
{{ $merged.z.a }} --> huey
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```
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Example 2
```go-html-template
{{ $merged := merge $m3 $m2 $m1 }}
{{ $merged.x }} --> foo
{{ $merged.y }} --> wibble
{{ $merged.z.a }} --> huey
```
Example 3
```go-html-template
{{ $merged := merge $m2 $m3 $m1 }}
{{ $merged.x }} --> foo
{{ $merged.y }} --> wobble
{{ $merged.z.a }} --> huey
```
Example 4
```go-html-template
{{ $merged := merge $m1 $m3 $m2 }}
{{ $merged.x }} --> bar
{{ $merged.y }} --> wibble
{{ $merged.z.a }} --> huey
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```
{{% note %}}
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Regardless of depth, merging only applies to maps. For slices, use [append ]({{< ref "functions/append" >}} ).
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{{% /note %}}