Path: csiph.com!xmission!news.snarked.org!border2.nntp.dca1.giganews.com!nntp.giganews.com!news.iecc.com!.POSTED.news.iecc.com!nerds-end From: Lasse =?iso-8859-1?q?Hiller=F8e?= Petersen Newsgroups: comp.compilers Subject: Re: How change grammar to equivalent LL(1) ? Date: 24 Apr 2020 16:21:04 GMT Organization: SunSITE.dk - Supporting Open source Lines: 34 Sender: news@iecc.com Approved: comp.compilers@iecc.com Message-ID: <20-04-009@comp.compilers> References: <19-12-023@comp.compilers> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Injection-Info: gal.iecc.com; posting-host="news.iecc.com:2001:470:1f07:1126:0:676f:7373:6970"; logging-data="54942"; mail-complaints-to="abuse@iecc.com" Keywords: parse, comment Posted-Date: 24 Apr 2020 12:42:38 EDT X-submission-address: compilers@iecc.com X-moderator-address: compilers-request@iecc.com X-FAQ-and-archives: http://compilers.iecc.com Xref: csiph.com comp.compilers:2512 I know this is a very late reply, however, I sometimes forget to read Usenet news for a while, I hope the moderator is forgiving. On Mon, 23 Dec 2019 05:57:50 -0500, Christopher F Clark wrote: > Just a slight comment on what Lasse Hillerĝe Petersen > wrote: > is called left-factoring. I am aware, however the point was having the refactored action return a function to adjust the direction of the parse tree. I am sure LISPers and Schemers wouldn't consider this anything special (so ordinary perhaps even, that I hadn't been able to find any written mention of it, until today), but when I wrote it back in 2017 I looked at my code and thought "hey, that's actually neat and general." Only today did I actually manage to find a paper, which, although I am very rusty in the matter of formal proofs and theory, being just an amateur hacker, to me reads like the theory behind "my" method: Thielecke, Hayo. (2012). Functional semantics of parsing actions, and left recursion elimination as continuation passing. PPDP'12 - Proceedings of the 2012 ACM SIGPLAN Principles and Practice of Declarative Programming. 91-102. 10.1145/2370776.2370789. > By the way, "Opt" is the usual suffix for Ety. Not in the Algol68 Reports IIRC. ;-) /Lasse [Your moderator tends to draw the line at replies to messages posted 15 or 20 years ago, generally via Google Groups. -John]