Typed Collections

You like Laravel Collections, but you don't use Laravel? You've used the Collections, but you feel like something missing? Like type hints? It's your package!, _(*1)

The problem

From PHP 7.0 you can typehint many things in php functions. Like:, _(*2)

function hello(string $name): string {
   return sprintf('Hello %s!', $name); 
}

But what if you want a string list? You can't typehint the content of arrays, you can only hint the array:, _(*3)

function hello(array $names): array;

And not like this:, _(*4)

function hello(array[string] $names): array[string];

It's sad., _(*5)

The solution

If you use this package, you can use type hinted Collections instead of simple arrays. Like this:, _(*6)

$names = new StringCollection(['Pete', 'Steve', 'John']);

function hello(StringCollection $names): StringCollection {
 ...
}

It's so simple!, _(*7)

Installation

composer require esemve/typed-collection

Types

You can use these default types: - ArrayCollection - BooleanCollection - CallableCollection - ClassCollection - FloatCollection - IntegerCollection - NullCollection - ObjectCollection - ResourceCollection - StringCollection, _(*8)

Create your own typed collection

If you want create your own typed collection, just create a new Collection file, and extend the AbstractTypedCollection. After this your only task is to fill the isValid function. It will check every added value, and if you try to add a value that is not allowed, the AbstractTypedCollection will automatically throw an InvalidTypedException., _(*9)

/// PostCollection.php:

<?php

declare(strict_types=1);

namespace Esemve\Collection;

use Entity\Post;

class PostCollection extends AbstractTypedCollection
{
    protected function isValid($element): bool
    {
        return $element instanceof Post;
    }
}

That's it. If you want to add your exception message, just add a getErrorMessage method to your class:, _(*10)

protected function getErrorMessage(): ?string
{
    return 'It\'s my own error message';
}

ClassCollection

There is a simple way to specify an 'instance of' typed collection:, _(*11)

$photo1 = new Photo();
$photo2 = new Photo();

$photoCollection = new ClassCollection(Photo::class, [$photo1, $photo2])

Use the Factory

If you want to, you can use the CollectionFactory. It helps you to create a collection if you don't want to hardcode the types to your code. If you use the CollectionFactory, you can use this methods from it:, _(*12)

createBooleanCollection(array $array): BooleanCollection;
createCallableCollection(array $array): CallableCollection;
createClassCollection(string $classname, array $array): ClassCollection;
createFloatCollection(array $array): FloatCollection;
createIntegerCollection(array $array): IntegerCollection;
createNullCollection(array $array): NullCollection;
createObjectCollection(array $array): ObjectCollection;
createResourceCollection(array $array): ResourceCollection;
createStringCollection(array $array): StringCollection;
createCollection(array $array): Collection;
create(PostCollection::class, $array): Collection (PostCollection just an example. It return a PostCollection)

In the factory you can remap the ::class classnames in the factory constructor param., _(*13)

Modifications

I've disabled the combine method from the original Collection class, because if you use that, your collection type can get mixed up., _(*14)

The keys() method always return a StringCollection., _(*15)

External package

You can use this package without Laravel, thanks to the "tightenco/collect" package that I've used.
If you use this package with Laravel, the tightenco package will automatically disable itself, and the TypedCollection will use the default Laravel Collection package., _(*16)