Talk:Canonical LR parser
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I'm still not sure if the naming is correct here. When I read "The dragon book" I get the impression that all the LR(k) with k >= 0 parsers are canonical parsers. -- Jan Hidders 14:14 Aug 18, 2002 (PDT)
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[edit] Canonicity
A canonical bottom-up parser reduces the leftmost phrase (aka the handle) of a sentential form. This is the case of most bottom-up parsing methods, including SLR(k), LALR(k) and LR(k) for k≥0. To be contrasted with noncanonical bottom-up parsers, where any phrase can be reduced (Tom Szymanski's PhD thesis is the best ressource I know on the subject available on the Internet).
I support the idea of having a separate page for LR(0), and suggest the Canonical LR page to be renamed LR(1) in consequence. -- Sylvain Schmitz 12:36 Aug 4, 2004 (GMT)
[edit] Not quite accurate
I think there's some confusion between canonical parsers and canonical parsing tables here. There are a number of algorithms for computing LR(k) parsing tables. The most general methods construct "canonical" parsing tables, faster methods build approximations, for example LALR(1).
[edit] Constructing LR(1) parsing tables
Where did this text come from? It looks cut-and-pasted. --P3d0 21:01, Dec 3, 2004 (UTC)
- Yep. From http://www.cse.uconn.edu/~akiayias/cse244fa04/N244-4-LR-more.ppt -- Jan Hidders 13:04, 4 Dec 2004 (UTC)
[edit] Same as/more than what?
The article is written as a comparison - "Goto is the same", "Reduce is more refined" etc. Same as what? More refined than what? IMO, those parts should be written as a full description perhaps followed by a comparison "This makes the reduce action more refined than the reduce operation in the <something>-parser". Perhaps the concept is most succinctly presented by comparison to other kinds of LR parsers rather than full description - but it should always be clear what you're comparing to. 85.194.50.194 11:19, 12 December 2006 (UTC)
