# ErrorException: Array to string conversion in /app/vendor/laravel/framework/src/Illuminate/Mail/Mailable.php ## 問題 code `$this->attachFromStorageDisk('s3', 'public/xxx/index.htm'));` ### error stack ``` #0 /app/vendor/laravel/framework/src/Illuminate/Mail/Mailable.php(844): Illuminate\Foundation\Bootstrap\HandleExceptions->handleError() #1 /app/vendor/laravel/framework/src/Illuminate/Collections/Collection.php(1512): Illuminate\Mail\Mailable->Illuminate\Mail\{closure}() #2 /app/vendor/laravel/framework/src/Illuminate/Collections/Traits/EnumeratesValues.php(840): Illuminate\Support\Collection->Illuminate\Support\{closure}() #3 [internal function]: Illuminate\Support\Collection->Illuminate\Support\Traits\{closure}() #4 /app/vendor/laravel/framework/src/Illuminate/Collections/Arr.php(717): array_filter() #5 /app/vendor/laravel/framework/src/Illuminate/Collections/Collection.php(358): Illuminate\Support\Arr::where() #6 /app/vendor/laravel/framework/src/Illuminate/Collections/Traits/EnumeratesValues.php(842): Illuminate\Support\Collection->filter() #7 /app/vendor/laravel/framework/src/Illuminate/Collections/Collection.php(1517): Illuminate\Support\Collection->reject() #8 /app/vendor/laravel/framework/src/Illuminate/Mail/Mailable.php(845): Illuminate\Support\Collection->unique() #9 /app/app/Mail/CommitMail.php(50): Illuminate\Mail\Mailable->attachFromStorageDisk() ``` ### 推測解法 換成箭頭 - [:: vs ->](https://stackoverflow.com/questions/1224789/php-classes-when-to-use-vs)