> 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/string/stringreduce.md).

# StringReduce

Run the provided udf over all characters in a string to reduce the values to a single output

## Method Signature

```
StringReduce(list=[string], callback=[function:BiFunction], initialValue=[any], delimiter=[string], includeEmptyFields=[boolean], multiCharacterDelimiter=[boolean])
```

### Arguments

| Argument                  | Type                  | Required | Description                        | Default |
| ------------------------- | --------------------- | -------- | ---------------------------------- | ------- |
| `list`                    | `string`              | `true`   |                                    |         |
| `callback`                | `function:BiFunction` | `true`   | The callback to use for the test   |         |
| `initialValue`            | `any`                 | `false`  | The initial value of the reduction |         |
| `delimiter`               | `string`              | `false`  |                                    | `,`     |
| `includeEmptyFields`      | `boolean`             | `false`  |                                    | `false` |
| `multiCharacterDelimiter` | `boolean`             | `false`  |                                    | `true`  |

## Examples

### Full function

Reduce the string to a single value.

[Run Example](https://try.boxlang.io/?code=eJzLSS0pSS0qVrBVUEpMSk5JTVOy5krOyS8uLUoFimkoOOZVKmTmFRjqwFhGCpoKtnYK1VycRaklpUV5YFkFNbCUNVetNVd5UWZJqn9pSUFpiYZCcElRZl56UGpKaXKqhkIOxDIdBagNOgpKVUpA8zStuQCLXirm)

```java
letters = "abcdef";
closure = ( Any inp1, Any inp2 ) => {
	return inp1 & inp2;
};
writeOutput( StringReduce( letters, closure, "z" ) );

```

Result: zabcdef

### Member function

Reduce the string to a single value.

```java
letters = "abcdef";
closure = ( Any inp1, Any inp2 ) => {
	return inp1 & inp2;
};
writeOutput( letters.reduce( closure, "z" ) );

```

Result: zabcdef

### Additional Examples

[Run Example](https://try.boxlang.io/?code=eJxFjcEKwjAQRM%2FuVww5SAq56DVU8AsE%2F6CmqxRClM2uYov%2FbsGAt2HmMS%2BzKktFDzdc0shXFynlezXhtfM4ljeeQzbehX%2Feo0N%2FwEIbYTUpjcC2zZE%2BkV4yKZ9MH6YeVWUqtzOPltgj%2F6QBzRTgZrd%2BdpG%2BNo4uXg%3D%3D)

```java
letters = "abcdef";
closure = ( Any value1, Any value2 ) => {
	return value1 & value2;
};
writeOutput( stringReduce( letters, closure, "z" ) );

```

## Related

* [Ascii](/boxlang-language/reference/built-in-functions/string/ascii.md)
* [CamelCase](/boxlang-language/reference/built-in-functions/string/camelcase.md)
* [Char](/boxlang-language/reference/built-in-functions/string/char.md)
* [CharsetDecode](/boxlang-language/reference/built-in-functions/string/charsetdecode.md)
* [CharsetEncode](/boxlang-language/reference/built-in-functions/string/charsetencode.md)
* [Compare](/boxlang-language/reference/built-in-functions/string/compare.md)
* [CompareNoCase](/boxlang-language/reference/built-in-functions/string/comparenocase.md)
* [Find](/boxlang-language/reference/built-in-functions/string/find.md)
* [FindNoCase](/boxlang-language/reference/built-in-functions/string/findnocase.md)
* [FindOneOf](/boxlang-language/reference/built-in-functions/string/findoneof.md)
* [Insert](/boxlang-language/reference/built-in-functions/string/insert.md)
* [JSStringFormat](/boxlang-language/reference/built-in-functions/string/jsstringformat.md)
* [Justify](/boxlang-language/reference/built-in-functions/string/justify.md)
* [KebabCase](/boxlang-language/reference/built-in-functions/string/kebabcase.md)
* [LCase](/boxlang-language/reference/built-in-functions/string/lcase.md)
* [Left](/boxlang-language/reference/built-in-functions/string/left.md)
* [ListReduce](/boxlang-language/reference/built-in-functions/string/listreduce.md)
* [LJustify](/boxlang-language/reference/built-in-functions/string/ljustify.md)
* [LTrim](/boxlang-language/reference/built-in-functions/string/ltrim.md)
* [Mid](/boxlang-language/reference/built-in-functions/string/mid.md)
* [ParagraphFormat](/boxlang-language/reference/built-in-functions/string/paragraphformat.md)
* [PascalCase](/boxlang-language/reference/built-in-functions/string/pascalcase.md)
* [QueryStringToStruct](/boxlang-language/reference/built-in-functions/string/querystringtostruct.md)
* [ReEscape](/boxlang-language/reference/built-in-functions/string/reescape.md)
* [ReFind](/boxlang-language/reference/built-in-functions/string/refind.md)
* [reFindNoCase](/boxlang-language/reference/built-in-functions/string/refindnocase.md)
* [ReMatch](/boxlang-language/reference/built-in-functions/string/rematch.md)
* [reMatchNoCase](/boxlang-language/reference/built-in-functions/string/rematchnocase.md)
* [RemoveChars](/boxlang-language/reference/built-in-functions/string/removechars.md)
* [RepeatString](/boxlang-language/reference/built-in-functions/string/repeatstring.md)
* [Replace](/boxlang-language/reference/built-in-functions/string/replace.md)
* [ReplaceList](/boxlang-language/reference/built-in-functions/string/replacelist.md)
* [ReplaceListNoCase](/boxlang-language/reference/built-in-functions/string/replacelistnocase.md)
* [ReplaceNoCase](/boxlang-language/reference/built-in-functions/string/replacenocase.md)
* [ReReplace](/boxlang-language/reference/built-in-functions/string/rereplace.md)
* [reReplaceNoCase](/boxlang-language/reference/built-in-functions/string/rereplacenocase.md)
* [Reverse](/boxlang-language/reference/built-in-functions/string/reverse.md)
* [Right](/boxlang-language/reference/built-in-functions/string/right.md)
* [RJustify](/boxlang-language/reference/built-in-functions/string/rjustify.md)
* [RTrim](/boxlang-language/reference/built-in-functions/string/rtrim.md)
* [Slugify](/boxlang-language/reference/built-in-functions/string/slugify.md)
* [SnakeCase](/boxlang-language/reference/built-in-functions/string/snakecase.md)
* [SpanExcluding](/boxlang-language/reference/built-in-functions/string/spanexcluding.md)
* [SpanIncluding](/boxlang-language/reference/built-in-functions/string/spanincluding.md)
* [SQLPrettify](/boxlang-language/reference/built-in-functions/string/sqlprettify.md)
* [StringBind](/boxlang-language/reference/built-in-functions/string/stringbind.md)
* [StringEach](/boxlang-language/reference/built-in-functions/string/stringeach.md)
* [StringEndsWith](/boxlang-language/reference/built-in-functions/string/stringendswith.md)
* [StringEndsWithNoCase](/boxlang-language/reference/built-in-functions/string/stringendswithnocase.md)
* [StringEvery](/boxlang-language/reference/built-in-functions/string/stringevery.md)
* [StringFilter](/boxlang-language/reference/built-in-functions/string/stringfilter.md)
* [StringMap](/boxlang-language/reference/built-in-functions/string/stringmap.md)
* [StringReduceRight](/boxlang-language/reference/built-in-functions/string/stringreduceright.md)
* [StringSome](/boxlang-language/reference/built-in-functions/string/stringsome.md)
* [StringSort](/boxlang-language/reference/built-in-functions/string/stringsort.md)
* [StringStartsWith](/boxlang-language/reference/built-in-functions/string/stringstartswith.md)
* [StringStartsWithNoCase](/boxlang-language/reference/built-in-functions/string/stringstartswithnocase.md)
* [StripCR](/boxlang-language/reference/built-in-functions/string/stripcr.md)
* [Trim](/boxlang-language/reference/built-in-functions/string/trim.md)
* [UCase](/boxlang-language/reference/built-in-functions/string/ucase.md)
* [UCFirst](/boxlang-language/reference/built-in-functions/string/ucfirst.md)
* [Val](/boxlang-language/reference/built-in-functions/string/val.md)
* [Wrap](/boxlang-language/reference/built-in-functions/string/wrap.md)
* [YesNoFormat](/boxlang-language/reference/built-in-functions/string/yesnoformat.md)


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