The Ds\Sequence::map() function is an inbuilt function in PHP which returns the result after applying callback function to each value.
Syntax:
Ds\Sequence abstract public Ds\Sequence::map( $callback )
Parameter: This function accepts single parameter $callback. The callback apply on each value of sequence.
Return Value: This function returns the callback after applying on each value.
Below programs illustrate the Ds\Sequence::map() function in PHP:
Program 1:
<?php // Create new sequence $seq = new \Ds\Vector( [4, 8, 12, 16] ); // Use map() function and display it var_dump( $seq ->map( function ( $val ) { return $val * 3; })); ?> |
Output: object(Ds\Vector)#3 (4) { [0]=> int(12) [1]=> int(24) [2]=> int(36) [3]=> int(48) }
Program 2:
<?php // Create new sequence $seq = new \Ds\Vector([12, 15, 18, 20]); // Use map() function and display it var_dump( $seq ->map( function ( $val ) { return $val / 3; })); ?> |
Output:
object(Ds\Vector)#3 (4) { [0]=> int(4) [1]=> int(5) [2]=> int(6) [3]=> float(6.6666666666667) }
Reference: http://php.net/manual/en/ds-sequence.map.php