From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 05420C47258 for ; Wed, 17 Jan 2024 08:23:07 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rQ1CN-0000fr-Pm; Wed, 17 Jan 2024 03:22:59 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rQ1CM-0000fZ-K7 for qemu-devel@nongnu.org; Wed, 17 Jan 2024 03:22:58 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rQ1CL-0006ED-5K for qemu-devel@nongnu.org; Wed, 17 Jan 2024 03:22:58 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1705479776; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=4aSEx0fvNwllNY6iFgw2sCLA+IXOhxEvm1hxlo78E0Q=; b=WSnSXmp+fqe9iDWKFMqn3wYm6KK6pSxEsZujeSBsrJOA0qhtXKHZsOnrs7M3LXSwmGGsC0 pBdD6oRUTrovwxHZfBDRS4lOfqIttC8dXPaODhk5nLBTkTrKXTXR2wXGdoAIeDXIDbbuvn E+lHAKpOew89zKrvs//DczmItzVvLBs= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-326-fxsnE0LfPxeulzVkTw06GQ-1; Wed, 17 Jan 2024 03:22:53 -0500 X-MC-Unique: fxsnE0LfPxeulzVkTw06GQ-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id C64842837800; Wed, 17 Jan 2024 08:22:52 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.39.192.128]) by smtp.corp.redhat.com (Postfix) with ESMTPS id A3FFE1C066AB; Wed, 17 Jan 2024 08:22:52 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id D596321E680D; Wed, 17 Jan 2024 09:22:49 +0100 (CET) From: Markus Armbruster To: John Snow Cc: qemu-devel@nongnu.org, Michael Roth , Peter Maydell Subject: Re: [PATCH v2 14/19] qapi/schema: fix typing for QAPISchemaVariants.tag_member In-Reply-To: <20240112222945.3033854-15-jsnow@redhat.com> (John Snow's message of "Fri, 12 Jan 2024 17:29:40 -0500") References: <20240112222945.3033854-1-jsnow@redhat.com> <20240112222945.3033854-15-jsnow@redhat.com> Date: Wed, 17 Jan 2024 09:22:49 +0100 Message-ID: <87h6jcnzc6.fsf@pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.7 Received-SPF: pass client-ip=170.10.133.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -38 X-Spam_score: -3.9 X-Spam_bar: --- X-Spam_report: (-3.9 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1.806, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org John Snow writes: > There are two related changes here: > > (1) We need to perform type narrowing for resolving the type of > tag_member during check(), and > > (2) tag_member is a delayed initialization field, but we can hide it > behind a property that raises an Exception if it's called too > early. This simplifies the typing in quite a few places and avoids > needing to assert that the "tag_member is not None" at a dozen > callsites, which can be confusing and suggest the wrong thing to a > drive-by contributor. > > Signed-off-by: John Snow I explored another solution, and posted it in reply to v2. If we decide not to like it better, I guess we'll go with this one.