John Chambers
2003-May-08 22:24 UTC
[Rd] 1. Performance fix in as(); 2. low-level access functions
1. A bug was found & fixed in the as() function that prevented it from caching methods; in some examples there would be a big performance penalty (found in investigating slow performance of the R DBI package). The fix has been committed to r-patched and r-devel. Thanks to David James for pointing out the problem. 2. A number of low-level access functions are being phased out. They were inconsistent and seemed to cause some confusion. For internal use, they have been replaced with direct access to slots in the class definition. The more useful of the properties have higher-level versions that work better (users were getting confused, e.g., between the high-level extends() and low-level getExtends()). All the low-level functions are equivalent to slot access, some with out-of-date names, going back to the early work on the methods package. See ?getExtends in the r-devel version for a list of the functions and the corresponding slots. Barring protests, the functions will be deprecated shortly. John --- John M. Chambers jmc@bell-labs.com Bell Labs, Lucent Technologies office: (908)582-2681 700 Mountain Avenue, Room 2C-282 fax: (908)582-3340 Murray Hill, NJ 07974 web: http://www.cs.bell-labs.com/~jmc