# libtmux.data/one-or-none

- **Module:** libtmux.data
- **Package:** io.github.libtmux:libtmux-clojure
- **Language:** Clojure
- **Kind:** function
- **Source:** https://github.com/libtmux/libtmux-java/blob/5f88402151ff08fc0390dd438b90963692ec3fe4/libtmux-clojure/src/main/clojure/libtmux/data.clj#L20
- **Public owner:** libtmux.data
- **Page:** https://libtmux.org/en/clojure/latest/reference/libtmux-data-one-or-none/

```
(one-or-none values)
```

Returns the only value, `nil` for none, or throws for multiple values.

Stops requesting matches once ambiguity is known. Finding zero or one may
scan all input; chunked producers may realize more. `nil` and `false` are values.
Use [[exactly-one]] when zero matches must also fail.

## Parameters

- `values`