krak/coll

PHP Collections Library

Coll (Collections)

The Collections library is yet another attempt to generate OO collections in php., _(*1)

Currently, the only collection in here is the Set because that's the only collection PHP actually is missing., _(*2)

Installation

compose require krak/coll

Usage

Set

A set represents a set of unique values., _(*3)

There are two interfaces for the Set type: ConstSet and Set., _(*4)

Const sets allow read access only whereas Sets allow read write access., _(*5)

// const methods
public function get($value);
public function has($value);
public function count();
public function getIterator();

// non-const methods
public function add($value);
public function remove($value);

<?php

use Krak\Coll\Set;

$s1 = new Set\ArraySet();
// or
$s1 = Set\ArraySet::create([1,2,3]);

$s1->add(4);
$s2 = set\union($s1, Set\ArraySet::create([3,4]));

set\is_subset($s2, $s1); // returns true because s1 is a subset of s2

// if you need to store object values

// internally uses SplObjectStorage
$oset = new Set\ObjectSet();
$oset->add(new stdClass());

// if you need to store values that work as array keys
$hset = new Set\HashSet();
$hset->add(['a' => 1]);

// if you need to store any of those types of values
$aset = new Set\AnySet();
set\fill($aset, [1, [1], new stdClass()]);

Each is set does also work as an iterable and is countable, _(*6)

<?php

count($s1); // returns the count
foreach ($s1 as $val) {
    // iterate over the set values
}

For type hinting use, Set or ConstSet, _(*7)

<?php

use Krak\Coll\Set;

function operate_on_mutable(Set\Set $s1) {
    // ...
}

function operate_on_immutable(Set\ConstSet $s1) {
    // ...
}

As seen earlier, we do have several set operation functions., _(*8)

// similar to union, but can work with different typed set (AnySet and ArraySet)
function join(ConstSet $s1, ConstSet $s2, $factory = null);
// s1 + s2
function union(ConstSet $s1, ConstSet $s2);
// s1 * s2
function intersect(ConstSet $s1, ConstSet $s2);
// s1 - s2
function difference(ConstSet $s1, ConstSet $s2);
// compares to sets returns true if s2 is subset of s1
function is_subset(ConstSet $s1, ConstSet $s2);
// compares to sets returns true on equal
function equals(ConstSet $s1, ConstSet $s2);
// fills a set with values and returns it
function fill(Set $s1, $values);

In addition to the functional methods, there is an OO interface like so, _(*9)

<?php
$s1->union($s2)
    ->intersect($s3)
    ->difference($s4)
    ->equals($s5);