1. Introduction

1.1 Analyzing the class structure

This class has two attributes: content, and length.

Both have protected visibility, allowing you to use inheritance if you need to.

The content attribute stores all values added to the object, while the length attribute, stores the current size of the array, making unnecessary the use of the function count().

use Cajudev\Collection;

$collection = new Collection();

print_r($collection);

/*
   Cajudev\Collection Object
   (
      [content:protected] => Array
         (
         )

      [length:protected] => 0
   )
*/

1.2 Creating an instance from an array

You can initialize the object by passing an array to the constructor

use Cajudev\Collection;

$array = [1, '2', 'three' => 3];

$collection = new Collection($array);
print_r($collection);

/*
   Cajudev\Collection Object
      (
         [content:protected] => Array
            (
                  [0] => 1
                  [1] => 2
                  [three] => 3
            )
         [length:Cajudev\Collection:protected] => 3
      )
*/

1.3 Creating an instance from another Collection

You can also easily pass an object of this class as an argument for the constructor, it will be converted.

use Cajudev\Collection;

$oldCollection = new Collection([1, 2, 3, 4, 5]);

$newCollection = new Collection($oldCollection);

print_r($newCollection); exit;

/*
   Cajudev\Collection Object
      (
         [content:protected] => Array
            (
                  [0] => 1
                  [1] => 2
                  [2] => 3
                  [3] => 4
                  [4] => 5
            )

         [length:protected] => 5
      )
*/

1.4 Creating an instance from other objects

Other objects passed by parameter will be treated in a special way, being parsed internally.

Note that the visibility of attributes does not affect parsing.

use Cajudev\Collection;

$object = new Class() {
   private $lorem  = 1;
   protected $ipsum  = 2;
   public    $dolor  = 3;
};

$collection = new Collection($object);

print_r($collection);

/*
   Cajudev\Collection Object
      (
         [content:protected] => Array
            (
                  [lorem] => 1
                  [ipsum] => 2
                  [dolor] => 3
            )

         [length:protected] => 3
      )
*/