From nobody@digitalkingdom.org Thu Jul 13 09:36:10 2006 Received: with ECARTIS (v1.0.0; list lojban-list); Thu, 13 Jul 2006 09:36:11 -0700 (PDT) Received: from nobody by chain.digitalkingdom.org with local (Exim 4.62) (envelope-from ) id 1G14AK-0005Js-BT for lojban-list-real@lojban.org; Thu, 13 Jul 2006 09:35:52 -0700 Received: from py-out-1112.google.com ([64.233.166.179]) by chain.digitalkingdom.org with esmtp (Exim 4.62) (envelope-from ) id 1G14AI-0005Jk-84 for lojban-list@lojban.org; Thu, 13 Jul 2006 09:35:52 -0700 Received: by py-out-1112.google.com with SMTP id i49so328399pyi for ; Thu, 13 Jul 2006 09:35:48 -0700 (PDT) DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:to:subject:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=lEoy9szBI++HO99Q7Dpa2JmmXgN4418azsx9pYRtb1/7MKzT2C70zhYA09v5Kw36EEHWQqmtlkt8CsvQ09fXNUVoe8Ntq+sp6WukXe5o02qstSSrPBGR9yTBymceG76to0ZTFu9KdqYtLLJan1MMT2JzXvRebY1gNonpcDb0hNo= Received: by 10.35.21.1 with SMTP id y1mr920081pyi; Thu, 13 Jul 2006 09:35:47 -0700 (PDT) Received: by 10.35.14.17 with HTTP; Thu, 13 Jul 2006 09:35:46 -0700 (PDT) Message-ID: <925d17560607130935wc4a3a02n7dcba4ae1bd06f77@mail.gmail.com> Date: Thu, 13 Jul 2006 13:35:46 -0300 From: "=?ISO-8859-1?Q?Jorge_Llamb=EDas?=" To: lojban-list@lojban.org Subject: [lojban] Re: Is Lojban a CFG? (was Re: [lojban-beginners] Re: Enumerating in Lojban) In-Reply-To: <44B664C6.3010403@ropine.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20060713003616.GD18359@chain.digitalkingdom.org> <20060713013545.GF18359@chain.digitalkingdom.org> <20060713025542.GH18359@chain.digitalkingdom.org> <925d17560607130709u3fef60c5ubd8f638c795685c0@mail.gmail.com> <44B664C6.3010403@ropine.com> X-Spam-Score: -2.5 (--) X-archive-position: 12177 X-ecartis-version: Ecartis v1.0.0 Sender: lojban-list-bounce@lojban.org Errors-to: lojban-list-bounce@lojban.org X-original-sender: jjllambias@gmail.com Precedence: bulk Reply-to: lojban-list@lojban.org X-list: lojban-list On 7/13/06, Seth Gordon wrote: > > Both CFGs and PEGs define a grammar to be used in a parser, so they're > "what the listener needs", but the parsers that use them work in > different ways. All right, and they are also both "what the speaker needs" in order to produce grammatical strings. CFGs are written from the point of view of the speaker, and PEGs are written from the point of view of the listener, even though each can be used the other way. Would that be an acceptable way of putting it? > > If I'm not mistaken, for any CFG, there is a PEG that will accept all and > > only the strings generated by that CFG. If that's correct, then what > > Jonathan > > wants (a CFG for Lojban) is compatible with what Robin wants (a PEG for > > Lojban). At least in principle, because maybe the required PEG might be > > way too complicated to write. Or maybe not, we can at least try. > > CFG and PEG are not just two different ways to express the same grammar. Right, and I didn't say they were. But isn't it true that for any CFG, there is always a PEG that will accept all and only the strings generated by the CFG? (I know the reverse is not true, there are PEGs that do not correspond to any CFG.) mu'o mi'e xorxes To unsubscribe from this list, send mail to lojban-list-request@lojban.org with the subject unsubscribe, or go to http://www.lojban.org/lsg2/, or if you're really stuck, send mail to secretary@lojban.org for help.