W3C home > Mailing lists > Public > public-cwm-talk@w3.org > January to March 2009

Re: n3 grammar : ambiguity for integer and decimal

From: luc peuvrier at home <lc.pvrr@orange.fr>
Date: Sat, 21 Feb 2009 19:44:16 +0100
Message-ID: <8A66D5C15FB54A6D839E8EBB8FFCC63C@LUCIO>
To: <jos.deroo@agfa.com>
Cc: "DIG group" <diggers@csail.mit.edu>, "++jean marc vanel" <jeanmarc.vanel@gmail.com>, "cwm talk" <public-cwm-talk@w3.org>, <public-cwm-talk-request@w3.org>, "Yosi Scharf" <syosi@mit.edu>, "Tim Berners-Lee" <timbl@w3.org>
Jos,

You are right according to that is why Tim and Dan in http://www.w3.org/TeamSubmission/n3/#keywords 

I have this ambigous problems only because the parsing implementation I made whithout preprocessing.

Sorry to make a "bad spot"

Kind regards,
Luc Peuvrier
  ----- Original Message ----- 
  From: jos.deroo@agfa.com 
  To: lc.pvrr@orange.fr 
  Cc: DIG group ; ++jean marc vanel ; cwm talk ; public-cwm-talk-request@w3.org ; Yosi Scharf ; Tim Berners-Lee 
  Sent: Saturday, February 21, 2009 6:33 PM
  Subject: Re: n3 grammar : ambiguity for integer and decimal


  Luc, 

  > There is no problems with "@is", "@of", and "@a" 

  and I think that is why Tim and Dan in 
  http://www.w3.org/TeamSubmission/n3/#keywords 
  say that 

  [[ 
  The grammar is written as without reference to the keywords system at all, 
  on the assumption that the string has been preprocessed by a keyword processor 
  to put a "@" on all keywords and a ":" on all qnames in the default namespace. 
  ]] 


  Kind regards,

  Jos De Roo | Agfa HealthCare
  Senior Researcher | HE/Advanced Clinical Applications Research
  T  +32 3444 7618
  http://www.agfa.com/w3c/jdroo/

  Quadrat NV, Kortrijksesteenweg 157, 9830 Sint-Martens-Latem, Belgium
  http://www.agfa.com/healthcare 


        "luc peuvrier at home" <lc.pvrr@orange.fr> 
        Sent by: public-cwm-talk-request@w3.org 
        02/21/2009 05:56 PM 
       To "Tim Berners-Lee" <timbl@w3.org>  
              cc Jos De Roo/AMDUS/AGFA@AGFA, "cwm talk" <public-cwm-talk@w3.org>, "DIG group" <diggers@csail.mit.edu>, "Yosi Scharf" <syosi@mit.edu>, "++jean marc vanel" <jeanmarc.vanel@gmail.com>  
              Subject Re: n3 grammar : ambiguity for integer and decimal 

              

       




  Tim, 
    
  Thank you to take care of my spot. 
    
  An other ambiguity I discovered writing n3 parser that I did not mentionned is about "is" "of" and "a" keyword. 
  There is no problems with "@is", "@of", and "@a" since the @ make able to distinguish to a qname, it is not the case with "is" "of" and "a" keyword because it also match qname non terminal. 
    
  I have this since I have the following rules not in n3 grammar: 
  verb <- ( "is" | "@is" ) expression ( "of" | "@of" ) 
    
  for the entry  " :jmv is :guru of :luc ." 
    
  it match at the same time 
    
  simpleStatement 
    | 
    subject propertylist 
    |       | 
    |       verb object objecttail propertylisttail 
    |       |    |      |          |
   |       |    |      void       void
  :jmv      is   :guru 
    
  and 
    
  simpleStatement 
    | 
    subject propertylist 
    |       | 
    |       verb                  object objecttail propertylisttail 
    |       |                     |      |          | 
    |       "is" expression "of"  |      |          | 
    |       |    |          |     |      |          | 
  :jmv      is   :guru      of    :luc   void       void 
    
  so there is a shift/reduce conflict between 
  verb <- expression 
  and 
  verb <- is expression of 
    
  this can be solve saying qname can not have the value "is" "of" 
    
  Best regards 
  Luc Peuvrier 
    
  ----- Original Message ----- 
  From: Tim Berners-Lee 
  To: luc peuvrier at home 
  Cc: cwm talk ; DIG group ; Yosi Scharf 
  Sent: Saturday, February 21, 2009 12:40 AM 
  Subject: Re: n3 grammar : ambiguity for integer and decimal 

  Luc, thanks for spotting that. 

  It seems to make sense.  I have checked it in as the new n3.n3 


  Tim 

  On 2009-02 -12, at 18:26, luc peuvrier at home wrote: 

  Hi, 
    
  Looking for integer and decimal non terminal ( token ) definition on following n3 grammar specification: 
  http://www..w3.org/2000/10/swap/grammar/n3-report.html 
    
  and 
    
  http://www.w3.org/2000/10/swap/grammar/n3.n3 
    
  The ebnf definition for integer and decimal are: 
    
  integer : [-+]?[0-9]+ 
    
  decimal : [-+]?[0-9]+(\.[0-9])? 
    
  There is an ambiguity since "123" ( for example ) match integer and decimal 
    
  I propose 
  decimal : [-+]?[0-9]+\.[0-9]* 
    
  Width the above definition "123" match only integer, "123." match decimal. This look like C and Java standard for numéric constants 
    
  Best regards 
  Luc Peuvrier 
Received on Saturday, 21 February 2009 18:44:55 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Saturday, 21 February 2009 18:45:13 GMT