Grammar Changes

Peter Dalgaard BSA p.dalgaard@biostat.ku.dk
17 Aug 1998 23:32:50 +0200


Ross Ihaka <ihaka@stat.auckland.ac.nz> writes:

> 
> I would like to make a couple of small changes to the R grammar.
> At present, operators like ~, ==, !=, <, <=, >, >= are declared
> to be non-associative.  This means that things like
> 
> 	a < b <= c
> 
> produce a "syntax error" message when typed.
> 
> I would like to change the grammar so that these operators are
> left-associative.  I want to make this change so that mathematical
> annotation in the graphics will work a little better.
> 
> Interestingly, these operators are left-associative in S, so this
> would be a move toward compatibility.
> 
> Does anyone have any strong thoughts on this?

Sounds harmless enough to me. 

-- 
   O__  ---- Peter Dalgaard             Blegdamsvej 3  
  c/ /'_ --- Dept. of Biostatistics     2200 Cph. N   
 (*) \(*) -- University of Copenhagen   Denmark      Ph: (+45) 35327918
~~~~~~~~~~ - (p.dalgaard@biostat.ku.dk)             FAX: (+45) 35327907
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