HH\Map::lastKey

Description

public function lastKey(): ?Tk

Returns the last key in the current Map.

Return Values

  • ?Tk - The last key in the current Map, or null if the Map is empty.

Examples

This example shows how lastKey() can be used even when a Map may be empty:

<?hh

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

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

$m = Map {};
var_dump($m->lastKey());
Output
string(6) "yellow"
NULL