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: David Lovemore Newsgroups: comp.compilers Subject: Re: Supporting multiple input syntaxes Date: Sun, 16 Aug 2020 02:21:23 -0700 (PDT) Organization: Compilers Central Lines: 8 Sender: news@iecc.com Approved: comp.compilers@iecc.com Message-ID: <20-08-011@comp.compilers> References: <20-08-002@comp.compilers> <20-08-009@comp.compilers> <20-08-010@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="54378"; mail-complaints-to="abuse@iecc.com" Keywords: parse, errors Posted-Date: 16 Aug 2020 11:53:21 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:2563 My friend, reporting the furthest position examined by the parser I have useful in error cases as a simple stop gap when using a combinator approach. Thinking about it you kind of want to see the furthest failed position and the stack of rules above it. Such requires meta information when the code is written in the most natural way. For this reason and others I believe it is good to represent your grammar in data structures which is further in the direction of a compiler compiler tool (or compiler interpreter tool).