Returns the value at the specified key in the current collection

public function at(
  Tk $k,
): Tv;

If the key is not present, an exception is thrown. If you don't want an exception to be thrown, use get() instead.

$v = $vec->at($k) is semantically equivalent to $v = $vec[$k].


  • Tk $k - the key from which to retrieve the value.


  • Tv - The value at the specified key; or an exception if the key does not exist.