# tmux_filter:expr/0

- **Package:** libtmux_erlang
- **Language:** Erlang
- **Kind:** typealias
- **Source:** https://github.com/libtmux/libtmux-erlang/blob/d1b6308440cf9eb8f6647e7ae434bce60e849368/apps/libtmux_erlang/src/tmux_filter.erl#L42
- **Page:** https://libtmux.org/en/erlang/latest/reference/t-tmux_filter-expr-0/

```
-type expr() ::
          {all | any, [expr()]} |
          {negate, expr()} |
          {field, binary(), atom(), term()} |
          {relation, binary(), atom(), expr()} |
          {count, binary(), [{atom(), term()}]}.
```

Normalized data expressions with stable field IDs, used by internal planners; not the wire grammar.