The Ds\Deque::map() function is an inbuilt function in PHP which is used to return the Deque with each element modified on the basis of operation performed as per the callback function.
Syntax:
public Ds\Deque::map( $callback ) : Ds\Deque
Parameters: This function accepts single parameter $callback which contains the callable function on the operation to be performed on each element of the Deque.
Return Value: This function returns a Deque with each element modified.
Below programs illustrate the Ds\Deque::map() function in PHP:
Program 1:
<?php // Declare a Deque $deck = new \Ds\Deque([1, 2, 3, 4, 5, 6]);
echo ( "Elements of deque\n" );
// Display the Elements of Deque print_r( $deck );
// Deque after mapping each value as // per in the callable function print_r( $deck ->map( function ( $element ) {
// performing operation on each element
return $element * 10;
})); ?> |
Output:
Elements of deque Ds\Deque Object ( [0] => 1 [1] => 2 [2] => 3 [3] => 4 [4] => 5 [5] => 6 ) Ds\Deque Object ( [0] => 10 [1] => 20 [2] => 30 [3] => 40 [4] => 50 [5] => 60 )
Program 2:
<?php // Declare a Deque $deck = new \Ds\Deque([10, 20, 30, 40, 50, 60]);
echo ( "Elements of deque\n" );
// Display the Elements of Deque print_r( $deck );
// Deque after mapping each value as // per in the callable function print_r( $deck ->map( function ( $element ) {
// performing operation on each element
return $element / 10;
})); ?> |
Output:
Elements of deque Ds\Deque Object ( [0] => 10 [1] => 20 [2] => 30 [3] => 40 [4] => 50 [5] => 60 ) Ds\Deque Object ( [0] => 1 [1] => 2 [2] => 3 [3] => 4 [4] => 5 [5] => 6 )
Reference: http://php.net/manual/en/ds-deque.map.php