HH\Map::firstValue

Description

public function firstValue(): ?Tv

Returns the first value in the current Map.

Return Values

  • ?Tv - The first value in the current Map, or null if the Map is empty.

Examples

The following example gets the first value from a Map. An empty Map will return null as its first value.

<?hh

namespace Hack\UserDocumentation\API\Examples\Map\FirstValue;

$m = Map {
  'red' => '#ff0000',
  'green' => '#00ff00',
  'blue' => '#0000ff',
  'yellow' => '#ffff00',
};
var_dump($m->firstValue());

$m = Map {};
var_dump($m->firstValue());
Output
string(7) "#ff0000"
NULL