remotelyliving / php-collection

src/CollectionInterface.php

<?php

namespace RemotelyLiving\PHPCollection;

interface CollectionInterface extends \Traversable, \Countable, \IteratorAggregate, \Serializable, \JsonSerializable
{
    public function count(): int;

    public function map(callable $fn): self;

    public function filter(callable $fn): self;

    public function each(callable $fn): self;

    public function chunk(int $size, callable $fn): self;

    public function reverse(): self;

    public function reIndex(): self;

    /**
     * @return mixed|null
     */
    public function first();

    /**
     * @return mixed|null
     */
    public function last();

    /**
     * @param callable $fn
     * @param null     $initial

Are you sure the doc-type for parameter $initial is correct as it would always require null to be passed?

     *
     * @return mixed
     */
    public function reduce(callable $fn, $initial = null);

    public function unique(): self;

    public function diff(CollectionInterface $collection): self;

    public function merge(CollectionInterface $collection): self;

    public function union(CollectionInterface $collection): self;

    public function intersect(CollectionInterface $collection): self;

    public function sort(callable $comparator = null): self;

    public function kSort(callable $comparator = null): self;

    public function empty(): bool;

    public function all(): array;

    public function deferred(): \Generator;

    public function values(): array;

    public function equals(CollectionInterface $collection): bool;

    /**
     * @param string|int $offset
     *
     * @return bool
     */
    public function has($offset): bool;

    /**
     * @param mixed $value
     *
     * @return bool
     */
    public function contains($value): bool;

    public function some(callable $evaluation): bool;

    /**
     * @param string|int $offset
     * @param mixed|null $default
     *
     * @return mixed|null
     */
    public function get($offset, $default = null);

    /**
     * @return mixed
     */
    public function rand();

    /**
     * @param string|int ...$offset
     */
    public function unset(...$offset): self;

    /**
     * @param string|int $offset
     * @param mixed $value
     *
     * @return $this
     */
    public function set($offset, $value): self;

    /**
     * @param mixed $value
     */
    public function push($value): self;

    /**
     * @param mixed $values
     *
     * @return $this
     */
    public function unshift(...$value): self;
}