Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.98.2) (envelope-from ) id 1xBvvv-00000003Spn-2PIb for pgsql-hackers@arkaria.postgresql.org; Wed, 30 Sep 2026 15:09:23 +0000 Received: from localhost ([127.0.0.1] helo=malur.postgresql.org) by malur.postgresql.org with esmtp (Exim 4.98.2) (envelope-from ) id 1xBvvu-000000030K8-2Me3 for pgsql-hackers@arkaria.postgresql.org; Wed, 30 Sep 2026 15:09:22 +0000 Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29]) by malur.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.98.2) (envelope-from ) id 1xBvvu-000000030K0-17j2 for pgsql-hackers@lists.postgresql.org; Wed, 30 Sep 2026 15:09:22 +0000 Received: from mail-lf2-x10.google.com ([2a00:1450:4864:36::10]) by magus.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.98.2) (envelope-from ) id 1xBvvs-000000027UQ-0Uq7 for pgsql-hackers@lists.postgresql.org; Wed, 30 Sep 2026 15:09:21 +0000 Received: by mail-lf2-x10.google.com with SMTP id 2adb3069b0e04-5b8f490bb27so2997044e87.2 for ; Wed, 30 Sep 2026 08:09:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1790780959; x=1791385759; darn=lists.postgresql.org; h=in-reply-to:content-transfer-encoding:content-disposition :content-type:mime-version:references:message-id:subject:cc:to:from :date:from:to:cc:subject:date:message-id:reply-to:content-type; bh=ybkB57p7k6jttn0QWCq7H3oEgK4sZqzLXe88lhCyB3c=; b=WRbaY8Fxa4FB6FU5FAtDe0IOw7RyNKQtlGy4aQNWC2YpNfHr8UUSSTRp70KJNvl3g0 ThoO43pfMqaF/loFz89rn9Oo6sikjvn8SwegRZccR0Ai+DCs7ouCQo4vZfAHTAKStDQO kWJECjuRrG4+JZ6slUsE9kggE+mfoBAo3MPd8O5NZxHITpQ+CFVGowXXGBKv9oBUv0wl sZyGpie+MDpRr3iHlC1Iurs6o0TwbUL3N6+se7OxartWLPK6ud4qaEOExvRFeSXSyM5O TCjq6vrdzfguJ8CvrOs4Z/gRCKoEauPF2GEZgyRayEgI8NDItw+02bw9OEINwXur4i/Z Y44Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1790780959; x=1791385759; h=in-reply-to:content-transfer-encoding:content-disposition :content-type:mime-version:references:message-id:subject:cc:to:from :date:x-gm-gg:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to:content-type; bh=ybkB57p7k6jttn0QWCq7H3oEgK4sZqzLXe88lhCyB3c=; b=jUgC1zxH57iLRr8eniDH0Zm/dZAn3wNnkHFJ4ZhhliSUGts8iwwTevKrF4STAfYl2x 9AW/eDDHhSY+NxXuNLzKXRakE7ONEJ1sVN2htDGrAaR+idDyJ1BKxOjfNWwdtjUnYkd2 i33SCTvapQcRL5+r6czrZpYMkbbiewPX3xqwznq3qwlaf8/8OXhkfWLbFi6gc3/ZR2gw Jg2wXwa8QNb4uuDOwq7TfqQ5/nRdNUIjGInJEsQ4CzxM61yVvo1x8hID2pKPF64WcjrW DCPd7kFXVrx79f+NsK6gMkYOIB2ak1Ro3/4YyQwK73lJLpGumbaOVCmCrKfzbJB2/hAB GLpA== X-Forwarded-Encrypted: i=1; AKwUvByVQA+rkbN2RYxne5K6JezKUlnlNTvLDB0FcDD/ZBf0LZYfjW0L0pIzQZZKXyA4JRSAdSUpsOHcgPA+ThP4@lists.postgresql.org X-Gm-Message-State: AFq9FYLBv3YmwhKxAqIBhhmWpxtr9+xK2xR3RDdUFfBCQnSJhULA7EID 1xeqYSl4rzjKQG9y4pP7QYHaE7unaxF2O3OghDi2/9Ff7maDATZ1rVNC X-Gm-Gg: AYBFou2MZyaJMI8+YymEXR8JSqKH7BbcS7jtpw0qKI9as/pxDkMaAJkO3OGm67rFr3A TcLXZgNNSpw49aRseSCYKO+TUdWZohxaQMo8xhHtluXXmRBqSwagPPGwxjrzFCOx/bC7wl4QhP3 xiLnA/LYh9I5OX6bc0xaaQAS/C85AUkGvwTN5z479QKe7EWIypk8Y+BEq4s24Wx7ZNEE5G2OAfO Ar/NqTFzJHf7dkoansF1+i0rMQzNWuN1emEFSOBBSt7mU6pXlVZLLjVCogzRLGS5aYYv27mRo+D YxZS3Q8c6VIBoWWEnUnUEtyyywMvp7SRBadMquTwFBnDKfiFhkQSmUQKaNQBaWZSiJWSta12hMC hDaCDuijGcrQzAZYIbkLvxkUjWFAwefrfhAPFgB7kslITu7K60b+wH0P5Lpw36vrqSV3HcRwfKb B6MPO8rn/dq6zLPf8u4Z/owar0Htjz1E1Zy7+6UT2NJYO7CcirG74qBdhGhark7L9QXmJ97Fa4p rCKmPhsMl3O7M50i8iLWG3r3YxNGCYWipHKT+62go+oAR7Drui+0uHnguSEGNaGYak= X-Received: by 2002:a05:6512:6681:10b0:5ba:4283:8110 with SMTP id 2adb3069b0e04-5ba428381a5mr141570e87.50.1790780958730; Wed, 30 Sep 2026 08:09:18 -0700 (PDT) Received: from nathan ([158.106.207.106]) by smtp.gmail.com with ESMTPSA id 2adb3069b0e04-5ba42fc8155sm24131e87.84.2026.09.30.08.09.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 30 Sep 2026 08:09:17 -0700 (PDT) Date: Wed, 30 Sep 2026 11:09:14 -0400 From: Nathan Bossart To: Vik Fearing Cc: Zsolt Parragi , pgsql-hackers@lists.postgresql.org Subject: Re: Logical Implication Message-ID: References: <37c76707-e6fa-4ee3-b57f-aa0bf1b0bba8@postgresfriends.org> <9ab35dbb-d9a4-4c1e-bae2-7763ddeb720c@postgresfriends.org> <3d779ee0-6596-4dae-b79c-e35b237f83bf@postgresfriends.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <3d779ee0-6596-4dae-b79c-e35b237f83bf@postgresfriends.org> List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Archived-At: Precedence: bulk On Tue, Sep 29, 2026 at 11:51:39PM +0200, Vik Fearing wrote: > On 29/09/2026 22:23, Zsolt Parragi wrote: >> And +1 for using %nonassoc instead > > That's three now.  I'll prepare a new patch. Thanks. One other thing I'd like to explore a bit more is whether to make IMPLIES "round-trippable," at least to see how much more complicated it would be. (I'm happy to do this part BTW). -- nathan