The **`__construct()` method** of PHP’s `DS\Set` class uses a [traversable](https://www.php.net/manual/en/class.traversable.php) object or array of values to create a new instance of a `DS\Set` object.

The process is illustrated below.

#   
#  Syntax
The prototype of the `__construct()` method is shown below.

```php
public Ds\Set::__construct(mixed $values = [])
```
##   
## Parameters

The `__construct()` method accepts a single parameter, i.e., a traversable object or an array of values, to initialize the instance. The provided values may have any data type.

## Return value

The `__construct()` method returns the newly created `DS\Set` instance.

## Example 

The code below shows how the `__construct()` method works in PHP.

<?php

// create sets
$setOne = new \DS\Set();
$setTwo = new \Ds\Set([5, 10, 15]);
$setThree = new \Ds\Set([1, "abc", 10, 2, "efg"]);

// print sets
print_r($setOne);
print_r($setTwo);
print_r($setThree);

?>

#   
##   
### Output 
The code above produces the following output.

```PHP
Ds\Set Object
(
)
Ds\Set Object
(
[0] => 5
[1] => 10
[2] => 15
)
Ds\Set Object
(
[0] => 1
[1] => abc
[2] => 10
[3] => 2
[4] => efg
)
```

> Note: To run this program, you need to install [Data Structures](https://www.php.net/manual/en/book.ds.php) for PHP on your local machine.

## Explanation

The `__construct()` method is implicitly invoked whenever the `new` keyword is used to initialize a set instance.

The code above creates three unique set instances in lines 4 to 6. Each instance is initialized through the `new` keyword which invokes the `__construct()` method.

`setOne` is created as an empty set, `setTwo` contains three integer values, and `setThree` contains a mix of strings and integers. Each set is printed accordingly.

What is the DS\Set __construct() method in PHP?

The DS\Set __construct() method creates a DS\Set instance using a traversable object or array of values.