join

<?php     public function stageException(string $method, string $path, FilesystemOperationFailed $exception): void

    {

        $this->stagedExceptions[join('@', [$method, $path])] = $exception;

    }



    private function throwStagedException(string $method, $path): void

<?php     private function throwStagedException(string $method, $path): void

    {

        $method = preg_replace('~.+::~', '', $method);

        $key = join('@', [$method, $path]);



        if ( ! array_key_exists($key, $this->stagedExceptions)) {

            return;