# LibTmux.Query.CardinalityError

- **Package:** libtmux-haskell
- **Language:** Haskell
- **Kind:** data type
- **Source:** https://github.com/libtmux/libtmux-haskell/blob/663e212622a02aa74a9bdc8ff71e2b45fcb1d4d5/internal/LibTmux/Internal/Query.hs#L33
- **Page:** https://libtmux.org/en/haskell/latest/reference/libtmux-query-t-cardinalityerror/

```haskell
data CardinalityError
```

Selection cardinality without retaining observations or counting ambiguity.

## Instances

- instance [Eq](https://hackage.haskell.org/package/base-4.22.0.0/docs/Data-Eq.html#t:Eq) [`CardinalityError`](/en/haskell/latest/reference/libtmux-query-t-cardinalityerror/) ([Source](https://github.com/libtmux/libtmux-haskell/blob/663e212622a02aa74a9bdc8ff71e2b45fcb1d4d5/internal/LibTmux/Internal/Query.hs#L36))

- instance [Show](https://hackage.haskell.org/package/base-4.22.0.0/docs/Prelude.html#t:Show) [`CardinalityError`](/en/haskell/latest/reference/libtmux-query-t-cardinalityerror/) ([Source](https://github.com/libtmux/libtmux-haskell/blob/663e212622a02aa74a9bdc8ff71e2b45fcb1d4d5/internal/LibTmux/Internal/Query.hs#L36))

## Members

### Common operations

- [`AtLeastTwoMatches`](/en/haskell/latest/reference/libtmux-query-v-atleasttwomatches/) (data constructor): A second match exists; no complete count is computed.

### Other members

- [`NoMatches`](/en/haskell/latest/reference/libtmux-query-v-nomatches/) (data constructor): The selection is empty where one value was required.

## Referenced declarations

- [`LibTmux.Query.CardinalityError`](/en/haskell/latest/reference/libtmux-query-t-cardinalityerror/) (data type)