HH\Lib\Vec\keys
Returns a new vec containing the keys of the given KeyedTraversable
namespace HH\Lib\Vec;
function keys<Tk, Tv>(
KeyedTraversable<Tk, Tv> $traversable,
): vec<Tk>;
Time complexity: O(n) Space complexity: O(n)
Parameters
KeyedTraversable<Tk,
Tv> $traversable
Returns
vec<Tk>
Examples
$result = Vec\keys(dict[1 => 100, 33 => 400 ]);
print_r($result);
//result: [1, 33]
$result = Vec\keys(dict[]);
print_r($result);
//result: []