# LibTmux::FilterExpr#to_proc

- **Module:** LibTmux
- **Package:** libtmux
- **Language:** Ruby
- **Kind:** method
- **Source:** https://github.com/libtmux/libtmux-ruby/blob/da7b6191b9439e3c84fa1c9eeaa9168263ee7af4/gems/libtmux/lib/libtmux/criteria.rb#L101
- **Page:** https://libtmux.org/en/ruby/v0.1.1/reference/libtmux-filterexpr-to_proc/

```
def to_proc: () -> ^(untyped) -> bool
```

Behavior: Criteria.

Behavior contract: Criteria.