# LibTmux.Query.none

- **Package:** libtmux-haskell
- **Language:** Haskell
- **Kind:** function
- **Source:** https://github.com/libtmux/libtmux-haskell/blob/663e212622a02aa74a9bdc8ff71e2b45fcb1d4d5/internal/LibTmux/Internal/Query.hs#L205
- **Page:** https://libtmux.org/en/haskell/latest/reference/libtmux-query-v-none/

```haskell
none :: ToMany row child -> Expr child -> Expr row
```

Signature types: [`ToMany`](/en/haskell/latest/reference/libtmux-query-t-tomany/), [`Expr`](/en/haskell/latest/reference/libtmux-query-t-expr/).

Existential, universal or absent matching children. A known empty
 relationship yields False, True or True, respectively. The child expression
 applies to one child at a time; put conditions inside one [`allOf`](/en/haskell/latest/reference/libtmux-query-v-allof/) when the
 same child must satisfy them. Unavailable relationships remain errors.

## Referenced declarations

- [`LibTmux.Query.Expr`](/en/haskell/latest/reference/libtmux-query-t-expr/) (data type)
- [`LibTmux.Query.ToMany`](/en/haskell/latest/reference/libtmux-query-t-tomany/) (data type)

## Guides

Pages that discuss `none`.

- [Typed queries](/en/haskell/latest/guides/query/)