> For the complete documentation index, see [llms.txt](https://docs.atfinity.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.atfinity.io/rule-language/operators/unknown-operators/join_of_any.md).

# JOIN\_OF\_ANY

### Description

`JOIN_OF_ANY` is the flexible counterpart of [`JOIN`](/rule-language/operators/string-operators/join.md). It puts together the known elements in a list and ignores them if they are not known / provided yet.

### Examples

```
p is Person
JOIN_OF_ANY(
    [
        p.title,
        p.first_name, 
        p.middle_name, 
        p.last_name
    ], 
    ' '
)
```

This [expression](/rule-language/expressions.md) extracts the name components of a person, including title. If the [case](/guides/glossary/case.md) is about President (p.title) John (p.first\_name) Fitzgerald (p.middle\_name) Kennedy (p.last\_name), this expression has as output:

`'President John Fitzgerald Kennedy'`

If only a first and last name have been filled out in the case, the return of this `JOIN_OF_ANY` expression is:

`'John Kennedy'`

Had the expression used the `JOIN` operator instead, and only ‘John’ and ‘Kennedy’ are known values, the system would have asked users to provide the missing values ‘title’ and ‘middle\_name’, before giving you a result.\ <br>


---

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