++++++++++++++++++ FME2001: - Review reports for paper 65 +++++++++++++++++++++ - Dear author(s) : this file was extracted automatically from a very large - mailbox. In case you find any problem concerning mail encodings (or any - other kind of anomaly disturbing your understanding of the reviews) please - email any of the PC cochairs (pamela@research.att.com,jno@di.uminho.pt). ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ PAPER NUMBER: 65 CATEGORY: 2 TITLE: Transformations for Grammar Adaptation AUTHOR(S): Ralf L\"ammel -------------------------------------------------------------------------------- 1. Briefly SUMMARIZE the paper (2-3 lines): The paper describes a number of transformations applicable to grammars. It firsts describes a semantics for grammar fragments, then some basic transformations, then higher level transformations with specific semantic properties. 2. RELEVANCE: Please provide a rating of the paper's relevance to the FME Symposium, using the scale: 0 = Out of scope 1 = Marginal interest 2 = Minority interest 3 = Majority interest 4 = Outstanding interest Numeric Rating: 2 Please comment your rating: I am concerned about the usefulness of the exercise. The example in the introduction is not clear. Its incorrectness cannot be judged from one rule in isolation, so I can't tell what the actual error is. If this was just a slip, then the original grammar is wrong and I am not particularly interested, presumably, in the formal relation between the original and the corrected. I can see that I may be interested in recording what changes I made (and why) but that doesn't justify all this formal machinery. So I would like more explanation on this topic. Just what was being done, for example, in "recovering" the VS-COBOL-II grammar? 3. OVERALL RECOMMENDATION: Please provide a rating of the paper's acceptability, using the scale: 1 = Strong reject 2 = Weak reject 3 = Could go either way 4 = Weak accept 5 = Strong accept Numeric Rating: 3 NB: There should be a correlation between the two rates above. 4. CONFIDENCE LEVEL: Please provide a rating of your expertise in the area addressed by the paper, using the scale: 1 = Know virtually nothing about this area 2 = Not too knowledgeable, but I know a bit 3 = Know a moderate amount, about average I'd say 4 = Not my main area of work, but I know a lot about it 5 = My area of work, I know it extremely well Numeric Rating: 3 NB: PC members are responsible for ensuring that 1 is not used here. 5. ORIGINALITY. What is NEW and SIGNIFICANT in the work reported here? Comment: The idea of formally describing grammar transformations 6. How WORTHWILE is the goal of the authors? Comment: Unclear: see above. 7. How well is this goal EXPLAINED and JUSTIFIED? Comment: Insufficiently: see above. 8. TECHNICAL QUALITY. Are the technical parts (definitions, statements, specifications, proofs, algorithms, etc.) SOUND? Comment: I think so. 9. APPLICABILITY. If the work is primarily theoretical or conceptual, are the implications in terms of applicability adequately justified? If the paper is about a new formal technique, are satisfactory arguments presented in favor of the new technique? If a methodology is proposed, is it sound? If experimental results are presented, is their relevance justified? Comment: Not clear: see above. 10. PRESENTATION: Describe the QUALITY of the writing, including suggestions for changes where appropriate. Comment: The paper is very well written. The examples are well chosen and motivated. The discussion of why the transformations are defined in particular ways is very illuminating. (The paper is much better in the details than on the overall picture.) 11. Were there any formatting or mechanical problems with this paper?: no Are the figures and length acceptable?: yes Are the references correct?: yes 12. OTHER COMMENTS you believe would be useful to the author(s), including pointers to missing relevant work: Definition 4 seems to have a typo in it, as there is a duplicated term in the superscript. And later a change from "resolve" to "define" seems to have been only partly done. +++++++++++++++++++++ End of FME 2001 Paper Review Report ++++++++++++++++++++++ PAPER NUMBER: 65 CATEGORY: 2 TITLE: Transformations for Grammar Adaptation AUTHOR(S): Ralf L\"ammel -------------------------------------------------------------------------------- 1. Briefly SUMMARIZE the paper (2-3 lines): The paper presents a grammar transformation framework, in which operators for grammar adaption can be expressed. Three different kinds of operators on grammars are considered (refactoring, construction and destruction operators) and results on the semantics-preservation properties of these operators are discussed. The transformational approach has been applied in grammar recovery projects (e.g. in the recovery of the VS-COBOL-II grammar). 2. RELEVANCE: Please provide a rating of the paper's relevance to the FME Symposium, using the scale: 0 = Out of scope 1 = Marginal interest 2 = Minority interest 3 = Majority interest 4 = Outstanding interest Numeric Rating: 3 Please comment your rating: The approach described in the paper is a successful example of the application of formal methods in a project with industrial relevance (the author says that the VS-COBOL-II-grammar recovery project led to the first publicly available "relatively correct and complete" COBOL grammar). Moreover, the formal transformational approach seems to be very successful in terms of productivity (in this paper and the paper [11] co-authored by C.Verhoef the authors report that the time needed for the COBOL-grammar-recovery was small compared to other figures). Hence the paper is in full accordance with the theme of the conference (Formal Methods for Increased Software Productivity). 3. OVERALL RECOMMENDATION: Please provide a rating of the paper's acceptability, using the scale: 1 = Strong reject 2 = Weak reject 3 = Could go either way 4 = Weak accept 5 = Strong accept Numeric Rating: 4 NB: There should be a correlation between the two rates above. 4. CONFIDENCE LEVEL: Please provide a rating oof your expertise in the area addressed by the paper, using the scale: 1 = Know virtually nothing about this area 2 = Not too knowledgeable, but I know a bit 3 = Know a moderate amount, about average I'd say 4 = Not my main area of work, but I know a lot about it 5 = My area of work, I know it extremely well Numeric Rating: 3 NB: PC members are responsible for ensuring that 1 is not used here. 5. ORIGINALITY. What is NEW and SIGNIFICANT in the work reported here? Comment: the referee is not familiar with the current literature on grammar transformations. What is new in the paper also w.r.t. methods of transformational programming seems to be that adaptation operators are considered which are not strictly semantics- preserving. The referee thinks that the transformational approach for grammar adaptations is a significant contribution, since it has proved to be successful and productive in real grammar projects. 6. How WORTHWILE is the goal of the authors? Comment: the goal is to contribute to more discipline in grammar development by providing a formal framework for "grammar programming". The author advocates to use a transformational approach (as already known from transformational programming) also for grammar development. Since grammar engineering is an important activity in many software projects the goal seems worthwhile to the referee. 7. How well is this goal EXPLAINED and JUSTIFIED? Comment: the author motivates his transformational approach with the successful application in grammar recovery projects. For details on such projects and for an account of grammar (re-) engineering he refers to a joint paper with C.Verhoef [11]. The referee is of the opinion that considering the theme of the conference it would be advisable to include a short account on grammar recovery and its importance in reengineering projects into the present paper. 8. TECHNICAL QUALITY. Are the technical parts (definitions, statements, specifications, proofs, algorithms, etc.) SOUND? Comment: The paper is of high technical quality. Some minor details are mentioned under 12. 9. APPLICABILITY. If the work is primarily theoretical or conceptual, are the implications in terms of applicability adequately justified? If the paper is about a new formal technique, are satisfactory arguments presented in favor of the new technique? If a methodology is proposed, is it sound? If experimental results are presented, is their relevance justified? Comment: the applicability of the approach has been validated in real grammar recovery projects, like the recovery of the VS-COBOL-II grammar (see also 2. above) 10. PRESENTATION: Describe the QUALITY of the writing, including suggestions for changes where appropriate. Comment: the paper is written in a very clear and understandable way. 11. Were there any formatting or mechanical problems with this paper?: no Are the figures and length acceptable?: in some figures the size of the characters is very small Are the references correct?: as far as the referee checked, they are correct. 12. OTHER COMMENTS you believe would be useful to the author(s), including pointers to missing relevant work: 1) Since grammar recovery projects are an important application of the transformational approach, a short definition of "grammar recovery" should be given. 2) In footnote 7) in section 4.4 it is said that "Proofs of the properties in Figure 13, and of the correctness of some other subsequent statements are not very instructive. We prefer a semi-formal discussion". Will the proofs be contained in the full version of the paper, which is going to appear as a CWI technical report ? Or where else can the proofs be found ? A reference should be included in footnote 7. 3) Definition 4 (Embedding), second line the set in the superscript attached to [[n]]sub(gamma') looks strange since bottom(gamma') appears twice. To the referee it seems that one instance of bottom(gamma') has to be replaced by the set of looping nonterminals of gamma'. In the paragraph following Definition 4, line 5, there seems to be something missing after the words "a homogeneous". 4) Figure 8, Combinators, first line: the omega-symbol on the rhs appearing after the first occurrence of the restriction operator has to be replaced by the psi-symbol. +++++++++++++++++++++ End of FME 2001 Paper Review Report ++++++++++++++++++++++ PAPER NUMBER: 65 CATEGORY: 2 TITLE: Transformations for Grammar Adaptation AUTHOR(S): Ralf Lammel -------------------------------------------------------------------------------- 1. Briefly SUMMARIZE the paper (2-3 lines): The paper presents transformations of context-free grammar that model common shemes of hand-writing grammar adaptations. 2. RELEVANCE: Please provide a rating of the paper's relevance to the FME Symposium, using the scale: 0 = Out of scope 1 = Marginal interest 2 = Minority interest 3 = Majority interest 4 = Outstanding interest Numeric Rating: 3 Please comment your rating: The paper presents the use of formal methods in the context of context-free grammar adaptation. 3. OVERALL RECOMMENDATION: Please provide a rating of the paper's acceptability, using the scale: 1 = Strong reject 2 = Weak reject 3 = Could go either way 4 = Weak accept 5 = Strong accept Numeric Rating: 4 NB: There should be a correlation between the two rates above. 4. CONFIDENCE LEVEL: Please provide a rating oof your expertise in the area addressed by the paper, using the scale: 1 = Know virtually nothing about this area 2 = Not too knowledgeable, but I know a bit 3 = Know a moderate amount, about average I'd say 4 = Not my main area of work, but I know a lot about it 5 = My area of work, I know it extremely well Numeric Rating: 3 NB: PC members are responsible for ensuring that 1 is not used here. 5. ORIGINALITY. What is NEW and SIGNIFICANT in the work reported here? Comment: The author introduces three kind of grammar adaptations: refactoring, construction and destruction which formalise the grammar transformations usually performed by grammar writers. Such grammar combinators allow for the incremental development of grammars and reuse of grammar components/fragments. 6. How WORTHWILE is the goal of the authors? Comment: As the author refer in the conclusions: "grammars are not too much of a research topic". Nevertheless, the use of formal methods in this context can increase the productivity of grammar writers/maintainers. I would like to see in the paper the answers to the following questions: Can the grammar transformations be automatically mechanised? Can the transformation be used to transform a grammar into an equivalent one, but belonging to a different class? In practical examples, however, semantic functions are usually associated with grammars. Do the grammar transformations hold when grammars are extended with semantic functions? 7. How well is this goal EXPLAINED and JUSTIFIED? Comment: I found it difficult to follow this paper. First, the paper does not motivate the reader. Second, there are few examples explaining the presented techniques. I think that it would be much easier to follow the paper if a running example is introduced and used throughout the text. 8. TECHNICAL QUALITY. Are the technical parts (definitions, statements, specifications, proofs, algorithms, etc.) SOUND? Comment: In page 5 (fig 3) the notation for terminal symbols is not introduced. 9. APPLICABILITY. If the work is primarily theoretical or conceptual, are the implications in terms of applicability adequately justified? If the paper is about a new formal technique, are satisfactory arguments presented in favor of the new technique? If a methodology is proposed, is it sound? If experimental results are presented, is their relevance justified? Comment: In the introduction it is written that the presented grammar adaptations were used within a grammar recovery project (the COBOL grammar). However, no more mention to such experience/results is referred. You should give the effort figures you mention, that is, the effort of your transformations versus hand-written transformations. The author say that with these transformations a "relatively correct" (?!) grammar for COBOL was defined. Why not correct? 10. PRESENTATION: Describe the QUALITY of the writing, including suggestions for changes where appropriate. Comment: The paper is well written. 11. Were there any formatting or mechanical problems with this paper?: No Are the figures and length acceptable?: Yes Are the references correct?: Yes 12. OTHER COMMENTS you believe would be useful to the author(s), including pointers to missing relevant work: +++++++++++++++++++++ End of FME 2001 Paper Review Report ++++++++++++++++++++++