# LibTmux::WindowLinkSelection::one_or_undef

- **Module:** LibTmux
- **Package:** LibTmux
- **Language:** Perl
- **Kind:** method
- **Source:** https://github.com/libtmux/libtmux-perl/blob/352715a4fa66a96eed7763b90daaa536aa2f121d/packages/core/lib/LibTmux/Selection.pm#L120
- **Inherited from:** LibTmux::Selection
- **Page:** https://libtmux.org/en/perl/latest/reference/libtmux-windowlinkselection-one_or_undef/

```
sub one_or_undef($self, @criteria)
```

`one_or_undef($criteria?)` returns an entity or undef for absence. A second matching occurrence still throws [`MultipleMatches`](/en/perl/latest/reference/libtmux-x-multiplematches/).

## Methods

## Parameters

- `criteria`