Iterator

Iter.php

<?php

class Iter {

    private $arr;
    private $result;

    public function __construct($array) {
        $this->arr = $array;
    }

    public function get() {
        return $this->result;
    }

    public function getCurrent() {
        if ($this->result == null) return $this->arr;
        else return $this->result;
    }

    public function filter($callback) {
        $result = [];

        foreach($this->getCurrent() as $item) {
            if ($callback($item)) {
                $result[] = $item;
            }
        }

        $this->result = $result;

        return $this;
    }

    public function map($callback) {
        $result = [];
        foreach($this->getCurrent() as $item) {
            $result[] = $callback($item);
        }

        $this->result = $result;

        return $this;
    }
}