The Ds\Deque::apply() function is an inbuilt function in PHP which is used to update the values of Deque by performing operations as defined by the callback function.
Syntax:
public Ds\Deque::apply( $callback ) : void
Parameters: This function accepts single parameter $callback which holds the function define the operation to be performed on each element of the Deque.
Return value: This function does not return any value.
Below programs illustrate the Ds\Deque::apply() function in PHP:
Program 1:
<?php // Declare deque $deck = new \Ds\Deque([1, 2, 3, 4, 5, 6]); echo ( "\nElements in the deque are\n" ); // Display the deque elements print_r( $deck ); // Use apply() function to implement // the operation $deck ->apply( function ( $element ) { return $element * 10; }); echo ( "\nUpdated elements in the deque\n" ); // Display the deque elements print_r( $deck ); ?> |
Elements in the deque are Ds\Deque Object ( [0] => 1 [1] => 2 [2] => 3 [3] => 4 [4] => 5 [5] => 6 ) Updated elements in the deque Ds\Deque Object ( [0] => 10 [1] => 20 [2] => 30 [3] => 40 [4] => 50 [5] => 60 )
Program 2:
<?php // Declare deque $deck = new \Ds\Deque([10, 20, 30, 40, 50, 60]); echo ( "\nElements in the deque are\n" ); // Display the deque elements print_r( $deck ); // Use apply() function to implement // the operation $deck ->apply( function ( $element ) { return $element % 10; }); echo ( "\nUpdated elements in the deque\n" ); // Display the deque elements print_r( $deck ); ?> |
Elements in the deque are Ds\Deque Object ( [0] => 10 [1] => 20 [2] => 30 [3] => 40 [4] => 50 [5] => 60 ) Updated elements in the deque Ds\Deque Object ( [0] => 0 [1] => 0 [2] => 0 [3] => 0 [4] => 0 [5] => 0 )
Reference: http://php.net/manual/en/ds-deque.apply.php