Fluent arrays

[stancl]

Add a fluent array API:

[1, 2, 3]->map(function ($n) {
    return $n*2;
});

$odd = [1, 2, 3]->filter(function ($n) {
    return $n & 1;
});

$sum = [1, 2, 3]->reduce(function ($carry, $n) {
    return $carry + $n;
}, 0);


// chaining

$prices = $products->filter(function ($product) {
    return $product->category = 'foo';
})->map(function ($product) {
    return $product->price;
});

Implementation

-> calls to arrays could be wrapped in phpplus_arr(), which would return an instance of a class like this:

class PHPPlusArr
{
    /** @var array */
    public $array;

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

    public function toArray(): array
    {
        return $this->array;
    }

    public function map(callable $callback): self
    {
        return new static(array_map($callback, $this->array));
    }

    public function filter(callable $callback): self
    {
        return new static(array_filter($this->array, $callback));
    }

    public function reduce(callable $callback, $initial = null): self
    {
        return new static(array_reduce($this->array, $callback, $initial));
    }
}

Additionally, common methods like sum(), count(), etc can be made part of that class (as long as it doesn't grow to the size of Collection). An interesting solution, that would work for sum() and count() could be

public function __call($method, $args)
{
    return $method(...$args);
}