# StructInsert

Inserts a key/value pair in to a struct - with an optional overwrite argument

## Method Signature

```
StructInsert(struct=[modifiableStruct], key=[any], value=[any], overwrite=[boolean])
```

### Arguments

| Argument    | Type               | Required | Description                                                                  | Default |
| ----------- | ------------------ | -------- | ---------------------------------------------------------------------------- | ------- |
| `struct`    | `modifiableStruct` | `true`   | The target struct                                                            |         |
| `key`       | `any`              | `true`   | The struct key                                                               |         |
| `value`     | `any`              | `true`   | The value to assign for the specified key                                    |         |
| `overwrite` | `boolean`          | `false`  | Whether to overwrite the existing value if the key exists ( default: false ) | `false` |

## Examples

### Simple Example

Inserts a new key/value into the structure

[Run Example](https://try.boxlang.io/?code=eJwli1EKgzAQBb%2BbUzz2q4InqHgAaaFnSNtFA5qG3Q0i4t2N%2BjUwzEw%2BocUKd6PBByE8QB%2F5z5HqonhhPVUvzJHc1jg1yV%2FrorLYHZNPNWgMSalQ%2BEeoGjdLMH5nS7kk1%2FDk5RX0OlAd0Q6fbSUY)

```java
map = { 
	"hair" : "brown",
	"eyes" : "green"
};
structInsert( map, "lips", "red" );
writeOutput( structKeyList( map ) );

```

Result: eyes,lips,hair

### Overwrite Example

Throws exception when you try to add a duplicate key, when allowoverwrite parameter is false.

[Run Example](https://try.boxlang.io/?code=eJwljEEOgjAQRdfMKb6zgoQTSDyAK89Q6ygkUprpNNgQ7m7F1Ute%2Fvuzi7hgAzU8ukkZZ%2FBdlzVwX5UUSYd6qUhg2gcyLdioSabZ2zUkUWsxu9jjf1Cp8qh4uncSdAPt8M78iNaFAvl0v3zVyeSWLeZas6gueuJjTF80fCtJ)

```java
map = { 
	"hair" : "brown",
	"eyes" : "green"
};
try {
	structInsert( map, "hair", "red", false );
} catch (any ex) {
	writeOutput( "error!" );
}

```

Result: error!

### Additional Examples

[Run Example](https://try.boxlang.io/?code=eJxljs0KwjAQhM%2FNUyx7qlDoXelBKkhPCj14jkmgwWQjaWIO4rvbPwvF4%2BzMfjOctOWmhwrewLL6coM9oHUOC5Zdm%2FOonKYHss%2BBlSW0nUsgoveKAvD5l52ifeZg%2BF2ZCuutiQW8uK8WBbuJ0lCvfADBA2gKbgW1wUcRZjf%2FXQvAIThw0CqXcEFMQ9YEDUKTMFGqfsRuJx2X8qRDN5VyKZX8X%2FYFW0NWfw%3D%3D)

```java
animals = { 
	COW : "moo",
	PIG : "oink"
};
// Show current animals
Dump( label="Current animals", var=animals );
// Insert cat into animals
StructInsert( animals, "cat", "meow" );
// Show animals, now includes cat
Dump( label="Animals with cat added", var=animals );

```

## Related

* [StructAppend](/boxlang-language/reference/built-in-functions/struct/structappend.md)
* [StructClear](/boxlang-language/reference/built-in-functions/struct/structclear.md)
* [StructCopy](/boxlang-language/reference/built-in-functions/struct/structcopy.md)
* [StructDelete](/boxlang-language/reference/built-in-functions/struct/structdelete.md)
* [StructEach](/boxlang-language/reference/built-in-functions/struct/structeach.md)
* [StructEquals](/boxlang-language/reference/built-in-functions/struct/structequals.md)
* [StructEvery](/boxlang-language/reference/built-in-functions/struct/structevery.md)
* [StructFilter](/boxlang-language/reference/built-in-functions/struct/structfilter.md)
* [StructFind](/boxlang-language/reference/built-in-functions/struct/structfind.md)
* [StructFindKey](/boxlang-language/reference/built-in-functions/struct/structfindkey.md)
* [StructFindValue](/boxlang-language/reference/built-in-functions/struct/structfindvalue.md)
* [StructGet](/boxlang-language/reference/built-in-functions/struct/structget.md)
* [StructGetMetadata](/boxlang-language/reference/built-in-functions/struct/structgetmetadata.md)
* [StructIsCaseSensitive](/boxlang-language/reference/built-in-functions/struct/structiscasesensitive.md)
* [StructIsOrdered](/boxlang-language/reference/built-in-functions/struct/structisordered.md)
* [StructKeyArray](/boxlang-language/reference/built-in-functions/struct/structkeyarray.md)
* [StructKeyExists](/boxlang-language/reference/built-in-functions/struct/structkeyexists.md)
* [StructKeyList](/boxlang-language/reference/built-in-functions/struct/structkeylist.md)
* [StructKeyTranslate](/boxlang-language/reference/built-in-functions/struct/structkeytranslate.md)
* [StructMap](/boxlang-language/reference/built-in-functions/struct/structmap.md)
* [StructNew](/boxlang-language/reference/built-in-functions/struct/structnew.md)
* [StructNone](/boxlang-language/reference/built-in-functions/struct/structnone.md)
* [StructReduce](/boxlang-language/reference/built-in-functions/struct/structreduce.md)
* [StructSome](/boxlang-language/reference/built-in-functions/struct/structsome.md)
* [StructSort](/boxlang-language/reference/built-in-functions/struct/structsort.md)
* [StructToQueryString](/boxlang-language/reference/built-in-functions/struct/structtoquerystring.md)
* [StructToSorted](/boxlang-language/reference/built-in-functions/struct/structtosorted.md)
* [StructUpdate](/boxlang-language/reference/built-in-functions/struct/structupdate.md)
* [StructValueArray](/boxlang-language/reference/built-in-functions/struct/structvaluearray.md)


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