# tmux_filter:predicate/1

- **Package:** libtmux_erlang
- **Language:** Erlang
- **Kind:** function
- **Source:** https://github.com/libtmux/libtmux-erlang/blob/d1b6308440cf9eb8f6647e7ae434bce60e849368/apps/libtmux_erlang/src/tmux_filter.erl#L205
- **Page:** https://libtmux.org/en/erlang/latest/reference/tmux_filter-predicate-1/

```
predicate(Prepared)
-spec predicate(prepared()) ->
                   fun((tmux_model:row()) -> boolean()).
```

Return a Boolean function bound to the prepared observation context.

Rows outside that context raise {prepared_context_mismatch, Detail}. Regex
evaluation errors raise {filter_evaluation_failed, Detail}. Use `matches/2`
for tagged errors. This does not run callbacks.

## Parameters

- `Prepared` (`prepared()`)