```{index} single: unpairs; List::Util function ``` ```{index} single: List::Util::unpairs; Perl function ``` # unpairs Flatten a list of two-element arrayrefs into a key/value list. ## Synopsis ```perl my @kvlist = unpairs @pairs; my %hash = unpairs @pairs; ``` ## What you get back A flat list with exactly two elements per input arrayref: `[0]` becomes the key, `[1]` becomes the value. Missing elements and non-arrayref inputs pad with `undef` so that the result is always even-sized. ## Examples ```perl my @kv = unpairs [a => 1], [b => 2]; # ('a', 1, 'b', 2) my %h = unpairs pairs %other; # round-trip my @kv = unpairs sort { $a->[0] cmp $b->[0] } pairs %h; ``` ## Differences from upstream Fully compatible with upstream. ## See also - `pairs` — the inverse direction.