src/Identifier/CallbackIdentifier.php
protected function checkCallable()
    {
        $callback = $this->getConfig('callback');

        if (!is_callable($callback)) {
            throw new InvalidArgumentException(sprintf(
                'The `callback` option is not a callable. Got `%s` instead.',
                gettype($callback)
            ));
        }
    }
protected function checkCallable()
    {
        $callback = $this->getConfig('callback');

        if (!is_callable($callback)) {
            throw new InvalidArgumentException(sprintf(
                'The `callback` option is not a callable. Got `%s` instead.',
                gettype($callback)
            ));
        }
    }
protected function checkCallable ( ) { $ callback = $ this -> getConfig ( 'callback' ) ; if ( ! is_callable ( $ callback ) ) { throw new InvalidArgumentException ( sprintf ( 'The `callback` option is not a callable. Got `%s` instead.' , gettype ( $ callback ) ) ) ; } }
Check the callable option

@throws \InvalidArgumentException
@return void
Check the callable option