Haldayne\Boost improves the readability of PHP code that does a lot of array manipulation.† Using a fluent interface that wraps any collection-like data structure, you can build compact and readable expressions to manipulate the elements in that collection.

Map is the Boost wrapper around collection-like data. That means, you can create a map from any of these types:

The Map class gives you a fluent API on which you can solve many general array-problems, like map/reduce:

$words = new Map(array ('bee', 'bear', 'beetle'));
$length = $words
    ->map(function ($word) { return strlen($word); })
    ->reduce(function ($total, $length) { return $total + $length; })
;

There are a boatload of built-in functions that apply to all Maps: review the API for details. But there are also purpose-built classes that extend the API to specific use-cases:

// join words together
$words = new MapOfStrings([ 'bleak', 'house' ]);
echo $words->join(' ');

// or sum all the odd integers between 1 and 10
// (Note use of short-hand code in grep statement)
$nums = new MapOfInts(range(0, 10));
echo $nums->all('1 == $_0 % 2')->sum();

These purpose-built classes demonstrate another feature of Boost's Map: membership requirements. With these requirements, you can solve the "type-hint an array of Foo" problem. In the example below, the Bar constructor enforces that it takes only a collection of Foo instances:

class Foo { }

class Bar {
    public function __construct(MapOfFoo $foos) {
        $this->foos = $foos;
    }
}

class MapOfFoo extends \Haldayne\Boost\MapOfObjects {
    protected function allowed($value) { return $value instanceof Foo; }
}

† On the Boost roadmap are plans to also improve the readability of heavy string manipulation code.