Invoker

A utility for invoking callbacks, with an optional fallback callback. This helper is intended for situations when you dynamically are building a callback, to be executed at a later point.

• Basic Example
• Arguments
• Fallback
• Caveat

Basic Example

use \Aedart\Utils\Helpers\Invoker;

$callback = function () {
    return true;
};

$invoker = Invoker::invoke($callback);

// ...Later in your application
echo $invoker->call(); // true

Arguments

To provide arguments, use the with() method.

use \Aedart\Utils\Helpers\Invoker;

$invoker = Invoker::invoke($callback)
    ->with(1, 2, 3);

Fallback

You may also specify a fallback callback, in case that the core callback is not callable.

Note: Any arguments that are provided via width() are passed on to the fallback callback, if "core" callback is not callable!

use \Aedart\Utils\Helpers\Invoker;

$unknownCallback = null; // Edge-case

$invoker = Invoker::invoke($unknownCallback)
    ->fallback(function() {
        // E.g. do something else if "core" callback is not callable...
        throw new \RuntimeException('No callback provided');
    });

// ...Later in your application
echo $invoker->call(); // throws exception

Caveat

WARNING

If neither the "core" callback nor fallback are callable, then the invoker component will throw a RuntimeException when invoked.

use \Aedart\Utils\Helpers\Invoker;

$callback = null;
$fallback = null

// Throws RuntimeException
$result = Invoker::invoke($callback)
    ->fallback($fallback)
    ->call();