# query.private.Predicate.matches_one

- **Module:** query.private.Predicate
- **Package:** libtmux
- **Language:** Rust
- **Kind:** method
- **Source:** https://github.com/libtmux/libtmux-rs/blob/f0e37052c232636b61d095817046e6bfc8f2ca40/crates/libtmux/src/query/private.rs#L328
- **Page:** https://libtmux.org/en/rs/latest/reference/query-private-predicate-matches_one/

```
query.private.Predicate.matches_one(self, value: Option<&U>) -> bool
```

Match this relation predicate against one already-loaded value.

The `is` quantifier evaluates an existing value. An absent value,
another quantifier, or another predicate family returns `false`.

The [`crate::query::Filterable`] relation example executes this
method in a hand-written generated-code expansion.