From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sog-mx-2.v43.ch3.sourceforge.com ([172.29.43.192] helo=mx.sourceforge.net) by sfs-ml-2.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1RgBb8-0002ZI-1T for bitcoin-development@lists.sourceforge.net; Thu, 29 Dec 2011 08:44:26 +0000 Received-SPF: pass (sog-mx-2.v43.ch3.sourceforge.com: domain of mm.st designates 66.111.4.26 as permitted sender) client-ip=66.111.4.26; envelope-from=theymos@mm.st; helo=out2.smtp.messagingengine.com; Received: from out2.smtp.messagingengine.com ([66.111.4.26]) by sog-mx-2.v43.ch3.sourceforge.com with esmtps (TLSv1:AES256-SHA:256) (Exim 4.76) id 1RgBb6-0004Df-V9 for bitcoin-development@lists.sourceforge.net; Thu, 29 Dec 2011 08:44:25 +0000 Received: from compute4.internal (compute4.nyi.mail.srv.osa [10.202.2.44]) by gateway1.nyi.mail.srv.osa (Postfix) with ESMTP id 6AE8620F8B for ; Thu, 29 Dec 2011 03:44:19 -0500 (EST) Received: from web3.nyi.mail.srv.osa ([10.202.2.213]) by compute4.internal (MEProxy); Thu, 29 Dec 2011 03:44:19 -0500 Received: by web3.nyi.mail.srv.osa (Postfix, from userid 99) id 4715C4008B; Thu, 29 Dec 2011 03:44:19 -0500 (EST) Message-Id: <1325148259.14431.140661016987461@webmail.messagingengine.com> X-Sasl-Enc: UliXItH1rJzaUEtJxLdHhdjZWaIwpknyrSZkv/Q9eW4g 1325148259 From: "theymos" To: bitcoin-development@lists.sourceforge.net MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii" X-Mailer: MessagingEngine.com Webmail Interface In-Reply-To: References: Date: Thu, 29 Dec 2011 02:44:19 -0600 X-Spam-Score: -1.6 (-) X-Spam-Report: Spam Filtering performed by mx.sourceforge.net. See http://spamassassin.org/tag/ for more details. -1.5 SPF_CHECK_PASS SPF reports sender host as permitted sender for sender-domain 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (theymos[at]mm.st) -0.0 SPF_PASS SPF: sender matches SPF record -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature X-Headers-End: 1RgBb6-0004Df-V9 Subject: Re: [Bitcoin-development] Alternative to OP_EVAL X-BeenThere: bitcoin-development@lists.sourceforge.net X-Mailman-Version: 2.1.9 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 29 Dec 2011 08:44:26 -0000 On Thu, Dec 29, 2011, at 01:55 AM, roconnor@theorem.ca wrote: > The number of operations executed is still bounded by the number of > operations occurring in the script. With the OP_EVAL proposal the > script language becomes essentially Turing complete, with only an > artificial limit on recursion depth preventing arbitrary computation > and there is no way to know what code will run without executing it. Even if OP_EVAL allowed infinite depth, you'd still need to explicitly specify all operations performed, since there is no way of looping. I think that something like OP_EVAL will eventually be used to improve Script in a backward-compatible way (enable the disabled math ops, fix bugs, etc.), so the mechanism might as well be used now. The only advantage I see with OP_CODEHASH is that script ops won't need to be in Script "strings".