From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mp11.migadu.com ([2001:41d0:2:bcc0::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by ms0.migadu.com with LMTPS id YCoBGoDHHGIB8AAAgWs5BA (envelope-from ) for ; Mon, 28 Feb 2022 14:00:48 +0100 Received: from aspmx1.migadu.com ([2001:41d0:2:bcc0::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by mp11.migadu.com with LMTPS id GGucF4DHHGIrBAAA9RJhRA (envelope-from ) for ; Mon, 28 Feb 2022 14:00:48 +0100 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 aspmx1.migadu.com (Postfix) with ESMTPS id EEA7245160 for ; Mon, 28 Feb 2022 14:00:45 +0100 (CET) Received: from localhost ([::1]:49406 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nOfds-0001j5-Vc for larch@yhetil.org; Mon, 28 Feb 2022 08:00:45 -0500 Received: from eggs.gnu.org ([209.51.188.92]:52866) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nOfcO-0001P7-4F for guix-devel@gnu.org; Mon, 28 Feb 2022 07:59:12 -0500 Received: from [2a0c:e300::1] (port=33686 helo=hera.aquilenet.fr) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nOfcL-0007x8-Au for guix-devel@gnu.org; Mon, 28 Feb 2022 07:59:11 -0500 Received: from localhost (localhost [127.0.0.1]) by hera.aquilenet.fr (Postfix) with ESMTP id 193AB26E; Mon, 28 Feb 2022 13:59:04 +0100 (CET) X-Virus-Scanned: Debian amavisd-new at aquilenet.fr Received: from hera.aquilenet.fr ([127.0.0.1]) by localhost (hera.aquilenet.fr [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id h7bKwJQOFmI3; Mon, 28 Feb 2022 13:59:03 +0100 (CET) Received: from ribbon (unknown [IPv6:2a01:e0a:1d:7270:af76:b9b:ca24:c465]) by hera.aquilenet.fr (Postfix) with ESMTPSA id BD18D1A4; Mon, 28 Feb 2022 13:59:02 +0100 (CET) From: =?utf-8?Q?Ludovic_Court=C3=A8s?= To: Ricardo Wurmus Subject: Re: better error messages through assertions References: <87ilthoxvu.fsf@elephly.net> <87k0dv6ahq.fsf@elephly.net> X-URL: http://www.fdn.fr/~lcourtes/ X-Revolutionary-Date: 10 =?utf-8?Q?Vent=C3=B4se?= an 230 de la =?utf-8?Q?R?= =?utf-8?Q?=C3=A9volution?= X-PGP-Key-ID: 0x090B11993D9AEBB5 X-PGP-Key: http://www.fdn.fr/~lcourtes/ludovic.asc X-PGP-Fingerprint: 3CE4 6455 8A84 FDC6 9DB4 0CFB 090B 1199 3D9A EBB5 X-OS: x86_64-pc-linux-gnu Date: Mon, 28 Feb 2022 13:59:02 +0100 In-Reply-To: <87k0dv6ahq.fsf@elephly.net> (Ricardo Wurmus's message of "Tue, 15 Feb 2022 23:15:26 +0100") Message-ID: <87mtibdu5l.fsf@gnu.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Spamd-Bar: / X-Rspamd-Server: hera X-Rspamd-Queue-Id: 193AB26E X-Spamd-Result: default: False [0.53 / 15.00]; ARC_NA(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_THREE(0.00)[3]; TO_DN_SOME(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; MIME_GOOD(-0.10)[text/plain]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+]; R_MIXED_CHARSET(0.63)[subject]; RCVD_COUNT_TWO(0.00)[2]; RCVD_TLS_ALL(0.00)[]; MID_RHS_MATCH_FROM(0.00)[] X-Host-Lookup-Failed: Reverse DNS lookup failed for 2a0c:e300::1 (failed) Received-SPF: softfail client-ip=2a0c:e300::1; envelope-from=ludo@gnu.org; helo=hera.aquilenet.fr X-Spam_score_int: -4 X-Spam_score: -0.5 X-Spam_bar: / X-Spam_report: (-0.5 / 5.0 requ) BAYES_00=-1.9, RDNS_NONE=0.793, SPF_HELO_PASS=-0.001, SPF_SOFTFAIL=0.665, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: guix-devel@gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "Development of GNU Guix and the GNU System distribution." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: guix-devel@gnu.org Errors-To: guix-devel-bounces+larch=yhetil.org@gnu.org Sender: "Guix-devel" X-Migadu-Flow: FLOW_IN X-Migadu-Country: US ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=yhetil.org; s=key1; t=1646053246; h=from:from:sender:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:list-id:list-help: list-unsubscribe:list-subscribe:list-post; bh=2TeD8NDbQD7bYTcSyzzE/B3IL957RcM44X9bDrb9n/g=; b=nElJQQzjFpSm+MzjB+yOlArdCoGwwienWTNwW77Pwee6lsFlutGD15xYT48TA5Kbdzb5T9 AZfhmaDGTpcZOUlCSolwOXzI426KMyrsKGR6xMm1DQZ00g5HB4alftqVEV0QdwoSBgzzZz uZyiOw+ix/yGObayQ+4NXa7VNWtULw3b+ROS/iwtArCU0eheGV2/lQXORlZ/FBhoiUggQc fd9cUvZfwTRyVhghABoJYGJurU8EmccPNmE/kx7VBrV3EnqQdg4bWDRgN9wRrAUhyTsXrq AZ+jwhqVEpAKL7WQNO9nLaFQGhoNVUHXfr+Bo6J4+WcsC1+b+vJy9rHPtpszpw== ARC-Seal: i=1; s=key1; d=yhetil.org; t=1646053246; a=rsa-sha256; cv=none; b=NC3u+Hr9JMOgg4tdb/MFDuly2jSw1J/C4GSl2hHdyp7JOHL1uyuNl4wk9XvWYrBN+IPnWk gKoU481Mf3TmzQI50tOlUapTXYUgo+YES70s74kRbzCiKzMT6nOzW5GYRSncqSgIF8t5FX Omp9UTluvsZqm/alwRRgtPAANuXSljJdbVbF2j6WHNbkdnzebVn80VAt54u3wthrc3G1TQ 8X2k5BKHPYBzKaVcAPoYHaf/e14ElMSbrNKOJvhRNGtDPA0nyP509GcNSYI4BKC8ysan92 OmAavkSmkwrxdw5bZuV3ruTnbkXZl+5yEQ7kWOCAYWwnwPvwT/Y/5dHH8WkDVg== ARC-Authentication-Results: i=1; aspmx1.migadu.com; dkim=none; dmarc=pass (policy=none) header.from=gnu.org; spf=pass (aspmx1.migadu.com: domain of "guix-devel-bounces+larch=yhetil.org@gnu.org" designates 209.51.188.17 as permitted sender) smtp.mailfrom="guix-devel-bounces+larch=yhetil.org@gnu.org" X-Migadu-Spam-Score: -4.10 Authentication-Results: aspmx1.migadu.com; dkim=none; dmarc=pass (policy=none) header.from=gnu.org; spf=pass (aspmx1.migadu.com: domain of "guix-devel-bounces+larch=yhetil.org@gnu.org" designates 209.51.188.17 as permitted sender) smtp.mailfrom="guix-devel-bounces+larch=yhetil.org@gnu.org" X-Migadu-Queue-Id: EEA7245160 X-Spam-Score: -4.10 X-Migadu-Scanner: scn0.migadu.com X-TUID: 35f3gV6GGf8M Hi! Ricardo Wurmus skribis: > Philip McGrath writes: > >> As a Racketeer, I think you're half way to reinventing contracts. > > Yes, I was in fact thinking of contracts, but shied away from mentioning > them :) The reason is that I think we can cover a lot of distance with > just a few simple assertions to avoid plowing ahead on bad arguments. I=E2=80=99d very much like to have contracts. For record types, we have =E2=80=9Csanitizers=E2=80=9D right now, which we = could use to insert procedural type checks. It wouldn=E2=80=99t be as nice as proper declarative contracts though, unless we arrange to make them look like contracts. Thoughts? Ludo=E2=80=99.