The Ds\Set::contains() function is an inbuilt function in PHP which is used to check the given value exists in the set or not. This function compares the value and its type.
Syntax:
bool public Ds\Set::contains( $values )
Parameters: This function accepts a single or many values which need to check the value exist in the set or not.
Return value: If value exist in the set then it returns True otherwise returns False.
Below programs illustrate the Ds\Set::contains() function in PHP:
Program 1:
<?php   // Declare new Set $set = new \Ds\Set(['G', 'e', 'e', 'k', 's', 5, 2, 7]);   // Use contains() function to check elements // exist in the Set or not var_dump($set->contains('G'));      var_dump($set->contains('k'));     var_dump($set->contains('p'));      var_dump($set->contains(7));      var_dump($set->contains('5'));      ?>  |
Output:
bool(true) bool(true) bool(false) bool(true) bool(false)
Program 2:
<?php   // Declare new Set $set = new \Ds\Set(['G', 'e', 'e', 'k', 's', 5, 2, 7]);   // Use contains() function to check elements // exist in the Set or not var_dump($set->contains('G', 'e'));      var_dump($set->contains('k', 'e', 7));     var_dump($set->contains('p', '1'));      var_dump($set->contains(7, 1));      var_dump($set->contains('5', 5));      ?>  |
Output:
bool(true) bool(true) bool(false) bool(false) bool(false)
Reference: http://php.net/manual/en/ds-set.contains.php
