Iterable functions

This package provides functions to work with iterables, as you usually do with arrays:

• iterable_to_array()
• iterable_to_traversable()
• iterable_map()
• iterable_merge()
• iterable_reduce()
• iterable_filter()
• iterable_values()
• iterable_chunk()

iterable_to_array()

PHP offers an iterator_to_array() function to export any iterator into an array.

But when you want to transform an iterable to an array, the iterable itself can already be an array.

When using iterator_to_array() with an iterable, that happens to be an array, PHP will throw a TypeError.

If you need an iterable-agnostic function, try our iterable_to_array():

use function BenTools\IterableFunctions\iterable_to_array;

var_dump(iterable_to_array(new \ArrayIterator(['foo', 'bar']))); // ['foo', 'bar']
var_dump(iterable_to_array(['foo', 'bar'])); // ['foo', 'bar']

iterable_to_traversable()

Useful when you have a Traversable type-hint, and you don't know wether or not your argument will be an array or an iterator.

If your variable is already an instance of Traversable (i.e. an Iterator, an IteratorAggregate or a Generator), the function simply returns it directly.

If your variable is an array, the function converts it to an ArrayIterator.

Usage:

use function BenTools\IterableFunctions\iterable_to_traversable;

var_dump(iterable_to_traversable(['foo', 'bar'])); // \ArrayIterator(['foo', 'bar'])
var_dump(iterable_to_traversable(new \ArrayIterator(['foo', 'bar']))); // \ArrayIterator(['foo', 'bar'])

iterable_map()

Works like an array_map with an array or a Traversable.

use function BenTools\IterableFunctions\iterable_map;

$generator = function () {
    yield 'foo';
    yield 'bar';
};

foreach (iterable_map($generator(), 'strtoupper') as $item) {
    var_dump($item); // FOO, BAR
}

iterable_merge()

Works like an array_merge with an array or a Traversable.

use function BenTools\IterableFunctions\iterable_merge;

$generator1 = function () {
    yield 'foo';
};

$generator2 = function () {
    yield 'bar';
};

foreach (iterable_merge($generator1(), $generator2()) as $item) {
    var_dump($item); // foo, bar
}

iterable_reduce()

Works like an reduce with an iterable.

use function BenTools\IterableFunctions\iterable_reduce;

$generator = function () {
    yield 1;
    yield 2;
};

$reduce = static function ($carry, $item) {
    return $carry + $item;
};

var_dump(
    iterable_reduce($generator(), $reduce, 0))
); // 3

iterable_filter()

Works like an array_filter with an array or a Traversable.

use function BenTools\IterableFunctions\iterable_filter;

$generator = function () {
    yield 0;
    yield 1;
};

foreach (iterable_filter($generator()) as $item) {
    var_dump($item); // 1
}

Of course you can define your own filter:

use function BenTools\IterableFunctions\iterable_filter;

$generator = function () {
    yield 'foo';
    yield 'bar';
};

$filter = function ($value) {
    return 'foo' !== $value;
};


foreach (iterable_filter($generator(), $filter) as $item) {
    var_dump($item); // bar
}

iterable_values()

Works like an array_values with an array or a Traversable.

use function BenTools\IterableFunctions\iterable_values;

$generator = function () {
    yield 'a' => 'a';
    yield 'b' => 'b';
};

foreach (iterable_values($generator()) as $key => $value) {
    var_dump($key); // 0, 1
    var_dump($value); // a, b
}

iterable_chunk()

Here's an array_chunk-like function that also works with a Traversable.

use function BenTools\IterableFunctions\iterable_chunk;

$fruits = [
    'banana',
    'apple',
    'strawberry',
    'raspberry',
    'pineapple',
]
$fruits = (fn () => yield from $fruits)()
iterable_chunk($fruits, 2);

/*
  [
    ['banana', 'apple'],
    ['strawberry', 'raspberry'],
    ['pineapple'],
  ]
 */

Iterable fluent interface

The iterable function allows you to wrap an iterable and apply some common operations.

With an array input:

use function BenTools\IterableFunctions\iterable;
$data = [
    'banana',
    'pineapple',
    'rock',
];

$iterable = iterable($data)->filter(fn($eatable) => 'rock' !== $eatable)->map('strtoupper'); // Traversable of ['banana', 'pineapple']

With a traversable input:

use function BenTools\IterableFunctions\iterable;
$data = [
    'banana',
    'pineapple',
    'rock',
];

$data = fn() => yield from $data;

$iterable = iterable($data())->filter(fn($eatable) => 'rock' !== $eatable)->map('strtoupper'); // Traversable of ['banana', 'pineapple']

Array output:

$iterable->asArray(); // array ['banana', 'pineapple']

Installation

composer require bentools/iterable-functions:^2.0

For PHP5+ compatibility, check out the 1.x branch.

Unit tests

php vendor/bin/pest