> For the complete documentation index, see [llms.txt](https://boxlang.ortusbooks.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/list/listprepend.md).

# ListPrepend

Filters a delimted list and returns the values from the callback test

## Method Signature

```
ListPrepend(list=[string], value=[string], delimiter=[string], includeEmptyFields=[boolean], multiCharacterDelimiter=[boolean])
```

### Arguments

| Argument                  | Type      | Required | Description                                                    | Default |
| ------------------------- | --------- | -------- | -------------------------------------------------------------- | ------- |
| `list`                    | `string`  | `true`   | string list to filter entries from                             |         |
| `value`                   | `string`  | `true`   |                                                                |         |
| `delimiter`               | `string`  | `false`  | string the list delimiter                                      | `,`     |
| `includeEmptyFields`      | `boolean` | `false`  | boolean whether to include empty fields in the returned result | `false` |
| `multiCharacterDelimiter` | `boolean` | `false`  | boolean whether the delimiter is multi-character               | `false` |

## Examples

### Prepend to a List using the List member function

[Run Example](https://try.boxlang.io/?code=eJwrTs3MS0vNSfHJLC5RsFVQcs7JL05VCEnMyU4t0gnOLy1Q8EusylSy5ipGVYjM1csBEgFFqQWpeSkaCkoBpWlplQrBGZlFJUoKmtZc5UWZJan%2BpSUFpSUaKPpAkgBktCyy)

```java
seinfeldList = "Close Talker,Soup Nazi";
seinfeldList = seinfeldList.listPrepend( "Puffy Shirt" );
writeOutput( seinfeldList );

```

Result: "Puffy Shirt,Close Talker,Soup Nazi"

### Prepend to a List using a dash delimiter

[Run Example](https://try.boxlang.io/?code=eJwrzs9N9cksLlGwVVAy1DXSNdY1UbLmKkaI5gCpgKLUgtS8FA0FmLiOgpKBEpDQVVLQtOYqL8osSfUvLSkoLUEoAUkAADlxHIQ%3D)

```java
someList = "1-2-3-4";
someList = listPrepend( someList, "0", "-" );
writeOutput( someList );

```

Result: "0-1-2-3-4"

### Prepend to a List with Empty Fields On

CF2018+

[Run Example](https://try.boxlang.io/?code=eJwrzs9N9cksLlGwVVByS03S8U0s0nEsKFKy5ipGyOQAqYCi1ILUvBQNBZi4joKSjo5XYp4SiAEkSopKUxU0rbnKizJLUv1LSwpKSxCKQRIAUHoiJw%3D%3D)

```java
someList = "Feb,Mar,Apr";
someList = listPrepend( someList, ",,Jan", ",", true );
writeOutput( someList );

```

Result: ",,Jan,Feb,Mar,Apr"

### Prepend to a List with Empty Fields Off

CF2018+

[Run Example](https://try.boxlang.io/?code=eJwrzs9N9cksLlGwVVByS03S8U0s0nEsKFKy5ipGyOQAqYCi1ILUvBQNBZi4joKSjo5XYp6OjhKICSTSEnOKUxU0rbnKizJLUv1LSwpKSxDqQRIArBoiyg%3D%3D)

```java
someList = "Feb,Mar,Apr";
someList = listPrepend( someList, ",,Jan,,", ",", false );
writeOutput( someList );

```

Result: "Jan,Feb,Mar,Apr"

### Additional Examples

[Run Example](https://try.boxlang.io/?code=eJxVzU0KwjAQhuF9TjHMKoXBHKC4ELRQqCDkBNrOIpA%2Fkkn1%2BFaqC1ff5uN5jQHrQvYMl9f9s%2BpZnHBqkpto8K7KrXDmuGhA26qj6WSJfJuZiUi4ChLgGCsX4QWhg65XxsCVw4MLDC3O4lJUVcq0YXAEpHED0so%2FBfs9em4ha%2FgeD%2F%2FpwZWttOtvId86jw%3D%3D)

```java
// Simple Example
writeoutput( listPrepend( "Susi,LAS,,boxlang,,,test", "Inserted" ) );
// Member Function
strList = ",I,,love,boxlang,,";
writeDump( strList.listPrepend( "First" ) );

```

## Related

* [GetToken](/boxlang-language/reference/built-in-functions/list/gettoken.md)
* [ListAppend](/boxlang-language/reference/built-in-functions/list/listappend.md)
* [ListAvg](/boxlang-language/reference/built-in-functions/list/listavg.md)
* [ListChangeDelims](/boxlang-language/reference/built-in-functions/list/listchangedelims.md)
* [ListCompact](/boxlang-language/reference/built-in-functions/list/listcompact.md)
* [ListContains](/boxlang-language/reference/built-in-functions/list/listcontains.md)
* [ListContainsNoCase](/boxlang-language/reference/built-in-functions/list/listcontainsnocase.md)
* [ListDeleteAt](/boxlang-language/reference/built-in-functions/list/listdeleteat.md)
* [ListEach](/boxlang-language/reference/built-in-functions/list/listeach.md)
* [ListEvery](/boxlang-language/reference/built-in-functions/list/listevery.md)
* [ListFilter](/boxlang-language/reference/built-in-functions/list/listfilter.md)
* [ListFind](/boxlang-language/reference/built-in-functions/list/listfind.md)
* [ListFindNoCase](/boxlang-language/reference/built-in-functions/list/listfindnocase.md)
* [ListFirst](/boxlang-language/reference/built-in-functions/list/listfirst.md)
* [ListGetAt](/boxlang-language/reference/built-in-functions/list/listgetat.md)
* [ListGetEndings](/boxlang-language/reference/built-in-functions/list/listgetendings.md)
* [ListIndexExists](/boxlang-language/reference/built-in-functions/list/listindexexists.md)
* [ListInsertAt](/boxlang-language/reference/built-in-functions/list/listinsertat.md)
* [ListItemTrim](/boxlang-language/reference/built-in-functions/list/listitemtrim.md)
* [ListLast](/boxlang-language/reference/built-in-functions/list/listlast.md)
* [ListLen](/boxlang-language/reference/built-in-functions/list/listlen.md)
* [ListMap](/boxlang-language/reference/built-in-functions/list/listmap.md)
* [ListNone](/boxlang-language/reference/built-in-functions/list/listnone.md)
* [ListQualify](/boxlang-language/reference/built-in-functions/list/listqualify.md)
* [ListReduceRight](/boxlang-language/reference/built-in-functions/list/listreduceright.md)
* [ListRemoveDuplicates](/boxlang-language/reference/built-in-functions/list/listremoveduplicates.md)
* [ListRest](/boxlang-language/reference/built-in-functions/list/listrest.md)
* [ListSetAt](/boxlang-language/reference/built-in-functions/list/listsetat.md)
* [ListSome](/boxlang-language/reference/built-in-functions/list/listsome.md)
* [ListSort](/boxlang-language/reference/built-in-functions/list/listsort.md)
* [ListToArray](/boxlang-language/reference/built-in-functions/list/listtoarray.md)
* [ListTrim](/boxlang-language/reference/built-in-functions/list/listtrim.md)
* [ListValueCount](/boxlang-language/reference/built-in-functions/list/listvaluecount.md)
* [ListValueCountNoCase](/boxlang-language/reference/built-in-functions/list/listvaluecountnocase.md)


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