From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from PH7PR06CU001.outbound.protection.outlook.com (mail-westus3azon11010067.outbound.protection.outlook.com [52.101.201.67]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 747AF2FD1BF; Mon, 17 Nov 2025 17:15:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=52.101.201.67 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763399709; cv=fail; b=s6Qr+yskhgtxSOaBsMaI4HfoNo0DPvpPnOJ/q5xJY+48FXzWqacLPkL9OysfNhtt3OU6pR/wJ5R+PV4DhCsBJ1Zmcl4RR1X6Jm75g5tr+1oPIuxYsJc+JOHiwLXyR2Tb07OAS0pmbm0JrnlPYp8flQUjdM6PAj2sMwUBTaZxnEA= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763399709; c=relaxed/simple; bh=7h3gwy/XmnrP/3yTWMAFc/v3Q+KNjrlAh9rTvpfn4C8=; h=Date:From:To:CC:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=OITaczh61TxgEXYCLlILSPTrZg0ewK9fDv7yOwHTKPN9aLTiV8SRCc7QUSmgeMRU1l51Xw1SmYyEe9tsvF6C0IGKaxq8Fn/PxIb/dIUelcaQkGhHSkSkYec6wtVX1mGsJjVdL12f7xuverT7q8NxDQObrV9aHa58FRztqLdlPU8= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=nvidia.com; spf=fail smtp.mailfrom=nvidia.com; dkim=pass (2048-bit key) header.d=Nvidia.com header.i=@Nvidia.com header.b=s7pGu1uZ; arc=fail smtp.client-ip=52.101.201.67 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=nvidia.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=nvidia.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=Nvidia.com header.i=@Nvidia.com header.b="s7pGu1uZ" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=HZfMsa8gRVGbiE/9ZuBHFl4KJmI52MRXXAubazGAkJbqTgllyEZNX3vVHpFh7D25NjoLtBHL9njST0MTPBFDbN8u1esgqkHCK6waBZyx6pg/JNSvSs68fYYC5SEP4dwA+jQb+0d+VNjwWQ8HoL0g5G2YoqH6q9SdkKdzAlKCUihxl+b8uwSuCVMFSAJyX843JS+H/t9B1UpkH6Qglcn+qu399SRkzuQw0u1vATZ6pgEUKiOdCn6CcRKTBTjAb9MxtVNbI/79sHPVIn/Yr2eRXaYLZWYgiQxDaMflckro4m6HDMzaWmOJPIIjo/B8YzW1J50gxMv1oqWA59vd9e2q1A== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=7h3gwy/XmnrP/3yTWMAFc/v3Q+KNjrlAh9rTvpfn4C8=; b=w6KPy0ruaM4T6O2aNxkkeyrd9vuRw9eXELSS/RzfTu03aRdbQ4W0hkAejOLyPdq9fyOpaMlbXY8/XTOdRr9FNpEVQWt1NlcsKJEcb8CN61316gPpGvjdVmQWssj6KQ1I0+N5JS0y05dIUW3ha9FDC5huAwX4GxgLfwl6vccZD1TxAH7W4AzI5A6sDeB9F4qpwFltyF7ze3UqIQHuxkrScJYBUZgiEUCapClAjzMjH6q+pMh/Qkchg6hD3NJd9IVgmIEPRbifh0HAS7/iB2cZ3rVkMTHD8SSYr9UDjrpyj2JRXbKdcI2Cdd2g1f7QQBKWGJL5luuuBcFTD4mKgPuGrA== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass (sender ip is 216.228.117.160) smtp.rcpttodomain=gmail.com smtp.mailfrom=nvidia.com; dmarc=pass (p=reject sp=reject pct=100) action=none header.from=nvidia.com; dkim=none (message not signed); arc=none (0) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=Nvidia.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=7h3gwy/XmnrP/3yTWMAFc/v3Q+KNjrlAh9rTvpfn4C8=; b=s7pGu1uZKP5zK2rZ7UvNIhNTtVHCPi66VRYSr302m09tF4wnHBFjFYnucnqdw3TqdWLIhXYoqKIqTYYmwXvvhTwxyX9okAT+uaw60pIudHnEYki1kOogFGCa/yhCAHN5TgPteY0flJZYYnJw5rWuIM71UPA8ikXbM0aKg2cMfMgzQwhau3ENf3RSs/4vQxierMHcqEXxJHjLduQ4q9BmMda1Y0wYuqwGbIGFLz7BovC1uIrs+fM7q3e/h+NEyPJFisE8Anqa7ASZp29aqQD044ByorWBTRauGHjXHJ8WY+I/Df9DVLOZ74MuULrleJc/Bacd0AL1j8IOjsLQ0eY1gg== Received: from BY3PR04CA0021.namprd04.prod.outlook.com (2603:10b6:a03:217::26) by IA4PR12MB9833.namprd12.prod.outlook.com (2603:10b6:208:55b::16) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9320.22; Mon, 17 Nov 2025 17:15:04 +0000 Received: from CO1PEPF000044FD.namprd21.prod.outlook.com (2603:10b6:a03:217:cafe::e7) by BY3PR04CA0021.outlook.office365.com (2603:10b6:a03:217::26) with Microsoft SMTP Server (version=TLS1_3, cipher=TLS_AES_256_GCM_SHA384) id 15.20.9320.22 via Frontend Transport; Mon, 17 Nov 2025 17:14:36 +0000 X-MS-Exchange-Authentication-Results: spf=pass (sender IP is 216.228.117.160) smtp.mailfrom=nvidia.com; dkim=none (message not signed) header.d=none;dmarc=pass action=none header.from=nvidia.com; Received-SPF: Pass (protection.outlook.com: domain of nvidia.com designates 216.228.117.160 as permitted sender) receiver=protection.outlook.com; client-ip=216.228.117.160; helo=mail.nvidia.com; pr=C Received: from mail.nvidia.com (216.228.117.160) by CO1PEPF000044FD.mail.protection.outlook.com (10.167.241.203) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9366.1 via Frontend Transport; Mon, 17 Nov 2025 17:15:03 +0000 Received: from rnnvmail201.nvidia.com (10.129.68.8) by mail.nvidia.com (10.129.200.66) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.20; Mon, 17 Nov 2025 09:14:37 -0800 Received: from rnnvmail203.nvidia.com (10.129.68.9) by rnnvmail201.nvidia.com (10.129.68.8) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.20; Mon, 17 Nov 2025 09:14:37 -0800 Received: from inno-thin-client (10.127.8.12) by mail.nvidia.com (10.129.68.9) with Microsoft SMTP Server id 15.2.2562.20 via Frontend Transport; Mon, 17 Nov 2025 09:14:29 -0800 Date: Mon, 17 Nov 2025 19:14:27 +0200 From: Zhi Wang To: Tamir Duberstein CC: Alice Ryhl , , , , , , , , , , , , , , , , , , , , , , , , , , Subject: Re: [PATCH v6 RESEND 4/7] rust: io: factor common I/O helpers into Io trait Message-ID: <20251117191427.2923aebb.zhiw@nvidia.com> In-Reply-To: References: <20251110204119.18351-1-zhiw@nvidia.com> <20251110204119.18351-5-zhiw@nvidia.com> <20251114192719.15a3c1a7.zhiw@nvidia.com> Organization: NVIDIA X-Mailer: Claws Mail 4.3.1 (GTK 3.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: rust-for-linux@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-NV-OnPremToCloud: ExternallySecured X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CO1PEPF000044FD:EE_|IA4PR12MB9833:EE_ X-MS-Office365-Filtering-Correlation-Id: daf99444-3b32-4475-4f16-08de25fcd909 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|36860700013|1800799024|82310400026|7416014|376014|7053199007; X-Microsoft-Antispam-Message-Info: =?utf-8?B?ZzZ6Q0NoOFJhTVB2OWxaWEt1cFlET2oyQ1g5V2ZPVGxVL2xyZzFuSzl5N1BN?= =?utf-8?B?cjE3Q2taNlhOZm5hNkozVDVMMEJ5eEFMaXlWTHRxNXI0V0wrTjJoYkxyN0hI?= =?utf-8?B?WnRXL092dXVBRUs1NVg3V3pJZnl5cklSMjlzdmloNFhLM2w1c01YRXlYVUNs?= =?utf-8?B?MkU5dXQ0RkZISjBsaVhuVmwxMjRxN0FIVXh0a2dDSVB1UDFSUnJFblZoZ1ZC?= =?utf-8?B?aS9QQi9reHhXeWQ3c1c1Z1NpemVRekpkY1lKTHFFcHloRnl3U21zNEMwVGVL?= =?utf-8?B?VlpZcytNY1FMLzdxRVZjaWlFRTBJeGFaZEtCZUhDMDNseUp2Wm9KWnRCczht?= =?utf-8?B?UCtNblBTUnVtMEcydUFGc0xPajc0dWRwTWNCV1ZXTlVTcmVaWjhsemNLMDBq?= =?utf-8?B?MVdWN1Z0OW4vUzNQODZWNk5PUHFySmp6NlFrSjAvdU1yZUpZQWlyaS9TeUpx?= =?utf-8?B?MEhEbDJUWFE1WmdWelZvSmxXbGFRd24zcDNSc3JVVzNyN2R6SUlPZVVpQ0FJ?= =?utf-8?B?dnB0VHBRM2pReExndXdQZ3pKQWNEQzE1N2w3aDRpanBoSzB4ZnJ2M2JaZU9O?= =?utf-8?B?VW1ZMnRKYmhnVTNpS1gvU1Y1VnJFSG5OeE8yR0hUMmRML25hMGpsb2FJT1VH?= =?utf-8?B?VElEeGZZTWZabU1iNjMzQ1FmaER3Vk9iR3JPenZTQ1ZlVlF0QXE2MzV3bWZG?= =?utf-8?B?NzJidEJMcjdycnRneTlacWpSak9pcTdSbUJlNEIzdHBVc0dsSTduVnhPMGo5?= =?utf-8?B?T3doRVRUclFybG5zbjZzaG9VeVN5ang4Vkc2ZlhqRUJsTUlkNHJzSGtDbElk?= =?utf-8?B?THpvMnkzbFVWS3FWbSticExzemZNZEhkVkYzcDBvMFp0aUVOdDJkaGhhbzBQ?= =?utf-8?B?NlFGMWR4VFYySmg3RDBITUYvLy9INEU0a09vS1Q2MTFneGM5ZG9ycVN3cWJ1?= =?utf-8?B?bnZjdS9ZQXgvY0crd0dwcEExNEdPR0ZzRmVNYkM5VG1kUE1jQnRjWG04R0tx?= =?utf-8?B?YVoxYi9xZ2Nla1o0WEVpWlg2QWhBR01pV3d5TTlBRzhRMEpWc0lXM0lXWGYw?= =?utf-8?B?NHRjRkkxRGl0dnY3c3VtMExlTEZmQmI0VGdjbHF5aVNpTEgrYmM0bjF6N2ZI?= =?utf-8?B?Q3YrUko0ZFFTYVArVmdUUG1EL0tKTVErWUNFTEdoOXlNTnB2ZmgzQ21YMVNq?= =?utf-8?B?akljZ0xmU09hT3A1U2QvTmY5N2NCZXlibFczNmNYT1RiMFNRM21qdTR3ekhH?= =?utf-8?B?bGcvRlVsazRWOHVEUVdkVzlxMy9mb0VpWUQ4TUN4dlF1Rzc5eE5WdlBEUzBL?= =?utf-8?B?TDAyaWZDTitoc3cvSWthTjdzUzI5QmsyRGpjNEpYNG5KdE9QejNmY0VXYnhJ?= =?utf-8?B?U3VZQU9ZaElKOTRhNWpkSnUxZ001aWJwYVJsWTFiVWtPVmtrZDV6d0dDcmk3?= =?utf-8?B?a2k3bDVRQy9QQll6VkFPNHZDWWhTNkNkR2FrVVg5eVFwdnRnQm80NUM5R0tp?= =?utf-8?B?UjYwMFVsQkMvYVJ3bFRSVTB3VU5FRXk4YTNlUzJ2TnNHYjJwTlRPR1ozY3E1?= =?utf-8?B?c1JXUzhMZzA2bXpvZHhIYTEvQ3lhTitueXJCQVFFK04yRzdaemwzeVU5c3FL?= =?utf-8?B?MHoxN2graUVSaE50cmZobFdGdkZIMno2K2o5ZExWN1lJb0ZrdjUvcGo0UlZN?= =?utf-8?B?ZUk0S1lrZDJ3bVhwVFpLUFR4cEd4czVaREhISSsvUlhRenRQUDBJWWsrNC9w?= =?utf-8?B?dzFEMTZVQ2xGZmVYWWhsR1g3VUhzNHN6MnRVSDRTYzhwT3VvTXBPeEJYNjFV?= =?utf-8?B?MXZ6VEZ4aEUvTGNrZEdRZ0tzQnBNQkdVVjFqOGRVN3hIUUNpQmJaUHM4Q2la?= =?utf-8?B?czNySTdHclZhcC9ieERkNnBUdWxpNWVBUFNMSlRrckdXSDhHanNDVUViQWFj?= =?utf-8?B?WUlTb3pDcDg3VHJoTkZqRXhOU05YM3VIejl4dXdNV1lKY2RnRHYwUHNzZDJG?= =?utf-8?B?TzFDUFNwTTNtS0wxTklVcEdJVmVQd29ydVpIcDdmQ3hONHNXL0ZUUjN4VThp?= =?utf-8?B?UmxKeVZMVTJQT2lWNGRSdThvMi95SjJQbXJuWHh2eFlOZ1VsZ2dEYnZsYVBZ?= =?utf-8?Q?Pcjk=3D?= X-Forefront-Antispam-Report: CIP:216.228.117.160;CTRY:US;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:mail.nvidia.com;PTR:dc6edge1.nvidia.com;CAT:NONE;SFS:(13230040)(36860700013)(1800799024)(82310400026)(7416014)(376014)(7053199007);DIR:OUT;SFP:1101; X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 17 Nov 2025 17:15:03.5296 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: daf99444-3b32-4475-4f16-08de25fcd909 X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=43083d15-7273-40c1-b7db-39efd9ccc17a;Ip=[216.228.117.160];Helo=[mail.nvidia.com] X-MS-Exchange-CrossTenant-AuthSource: CO1PEPF000044FD.namprd21.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA4PR12MB9833 On Fri, 14 Nov 2025 13:53:01 -0500 Tamir Duberstein wrote: > On Fri, Nov 14, 2025 at 12:37=E2=80=AFPM Zhi Wang wrote: > > snip >=20 > What about using an associated Err type? In the infallible case, it > would be `core::convert::Infallible`. It would be slightly more > ergonomic if associated type defaults were stable[0], though. >=20 > [0] https://github.com/rust-lang/rust/issues/29661 Thanks, Tamir. From Alice's and Danilo=E2=80=99s discussion, it seems we=E2= =80=99ll keep the fallible and infallible traits separate for now. Still, I really like the idea of an associated Err type. Thanks for the trick. :) Z.