[datatable-help] v1.7.10 submitted to CRAN

[Matthew Dowle]

NEW FEATURES

o  New function setcolorder() reorders the columns by name
   or by number, by reference with no copy. This is (almost)
   infinitely faster than DT[,neworder,with=FALSE].
        
o  The prefix i. can now be used in j to refer to join inherited
   columns of i that are otherwise masked by columns in x with
   the same name.
        
        
BUG FIXES

o  tracemem() in example(setkey) was causing CRAN check errors
   on machines where R is compiled without memory profiling available,
   for efficiency. Notably, R for Windows, Ubuntu and Mac have memory
   profiling enabled which may slow down R on those architectures even
   when memory profiling is not being requested by the user. The call
   to tracemem() is now wrapped with try().
        
o  merge of unkeyed tables now works correctly after breaking in 1.7.8 
   and 1.7.9. Thanks to Eric and DM for reporting. Tests added.
        
o  nomatch=0 was ignored for the first group when j used join inherited
   scope. Fixed and tests added.
         

USER-VISIBLE CHANGES

o  Updating an existing column using := after a key<- now works without
   warning or error. This can be useful in interactive use when you
   forget to use setkey() but don't mind about the inefficiency of 
   key<-. Thanks to Chris Neff for providing a convincing use case. 
   Adding a new column using := after key<- issues a warning, 
   shallow copies and proceeds, as before.
    
o  The 'datatable.pre.suffixes' option has been removed. It was 
   available to obtain deprecated merge() suffixes pre v1.5.4.