Path: csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!news.glorb.com!news-out.readnews.com!news-xxxfer.readnews.com!news.misty.com!news.iecc.com!nerds-end From: spy974@gmail.com Newsgroups: comp.compilers Subject: Question about parser/parsing technics Date: Tue, 6 Mar 2012 05:21:30 -0800 (PST) Organization: Compilers Central Lines: 14 Sender: news@iecc.com Approved: comp.compilers@iecc.com Message-ID: <12-03-006@comp.compilers> NNTP-Posting-Host: news.iecc.com X-Trace: leila.iecc.com 1331059222 76148 64.57.183.58 (6 Mar 2012 18:40:22 GMT) X-Complaints-To: abuse@iecc.com NNTP-Posting-Date: Tue, 6 Mar 2012 18:40:22 +0000 (UTC) Keywords: parse, question Posted-Date: 06 Mar 2012 13:40:22 EST 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:473 Hi everyone, I was wondering if it exists a parser (fault tolerant) which can create an (maybe) incomplete concrete syntax tree according to an incomplete grammar ? Create only parts of the tree that it recognizes, and the rest are inside a token 'unknown' (or something else). informal & light example: grammar: - root -> Add - Add -> Int + Int - Int -> [0..9]+ for expression: "1 + 41" it will create a complete tree for expression: "1 + 3.14" it create a tree where the right operand of Add is (or tagged as) unrecognized. thanks for pointers you will give me.