vector/core

A functional programming library for PHP

v7.0.1 2020-03-10 01:24 UTC

Requires

• php: ^7.4

Requires (Dev)

• phpunit/phpunit: ^8.4

MIT

• Joseph Walker

• utility
• functional
• curry
• monad
• compose

README

The Elevator Pitch

Vector gives you php functional superpowers.

• The evolution:

  • Native PHP

      array_sum(
          array_map(
              fn($a) => $a + 1,
              [1, 2, 3]
          )
      );
      // 9

    • 👎 More than 1 or 2 function chains is unmaintainable
  • Laravel Collections

      collect([1, 2, 3])
          ->map(fn($a) => $a + 1)
          ->sum();
          // 9

    • 👍 More than 1 or 2 function chains is unmaintainable
    • 👎 Unfortunately you can't do this with every type in the same elegant way (only works with collections)
  • Vector

       vector([1, 2, 3])
           ->pipe(Arrays::map(Math::add(1))) // or `fn($a) => $a + 1)` 
           ->pipe(Math::sum())();
           // [2, 3, 4]

    • 👍 Works super similarly to collections, but just accepts & returns normal arrays (no ->toArray()-ing necessary)
    • 👍 Works super similarly to collections for everything else too!
    • 👎 Unfortunately it is an extra dependency (we don't have the native pipe operator yet https://wiki.php.net/rfc/pipe-operator-v2)

• You can add currying to any function, it isn't only limited to Vector built ins.

  • Module::curry('explode')(',')('a,b,c')(PHP_INT_MAX) // ['a', 'b', 'c']

PHP Version Support

• 8.0+

Install

composer require vector/core

Show Me Some More Code

More automatic currying.

$addOne = Arrays::map(Math::add(1));
$addOne([1, 2, 3]); // [2, 3, 4]

First class composition (Functional Pipelines).

$addSix = Lambda::compose(Math::add(4), Math::add(2)); // (Or ::pipe for the opposite flow direction)
$addSix(4); // 10;

Pattern Matching (Maybe & Result monads included).

Pattern::match([
    fn(Just $value) => fn ($unwrapped) => $unwrapped,
    fn(Nothing $value) => 'nothing',
])(Maybe::just('just')); // 'just'

Granular control flow (without try/catch).

$errorHandler = function (Err $err) {
    return Pattern::match([
        function (QueryException $exception) {
            Log::info($exception);
            return response(404);
        },
        function (DBException $exception) {
            Log::error($exception);
            return response(500);
        },
    ]);
};

return Pattern::match([
    fn(Ok $value) => fn (User $user) => $user,
    $errorHandler
])(Result::from(fn() => User::findOrFail(1)));

Make your own modules with auto-curried methods

use Vector\Core\Curry;
use Vector\Core\Module;

class MyModule
{
    use Module;
    
    #[Curry]
    protected static function myCurriedFunction($a, $b)
    {
        return $a + $b;
    }
}