Duncan Temple Lang <[EMAIL PROTECTED]> writes: > The HashFunc typedef in hashfuncs.h would be more flexible if it > took an additional argument of type void * to allow for user > defined data. Alternatively, it might take the hash table > object itself. The function might want to do some > updating of the table itself, or look at some table (e.g. for perfect > hashing). And if we had a place to provide additional information, it > is easy to allow the hash function object to be an R function.
Worth considering. I don't think perfect hashing is in scope here, but would need to give it more thought -- seems to me that perfect hashing would be better served by something separate. > Also, you are using a "global" table of hash functions > (i.e. Dict_HashFunctions) and looking up the C routine using > GET_HASHFUN > which is tied to the integer indexing for this global table. > Why not use the C routines directly from R, i.e. using > getNativeSymbolInfo and pass this from R to the newly created > dict. This avoids the lookup, the global table and makes things > extensible with routines in packages and simply extends to allowing > R functions to be passed instead of C routines. > It also removes the need to synchronize the labeling system in > R and in C, i.e. that 0L corresponds to PJW. The reliance on > synchronized names rather than direct handles is unnecessary > although widely used in S/R code. Why not? Only because I didn't think of it ;-) > I'm more than happy to give some code to illustrate what I mean > more precisely if you'd like it. Sure. At the same time, I'm a bit hesitant to invest further in dict until I get a sense of whether or not it might actually be useful to people. It's main use may turn out to be for investigating hash functions behavior and for a test tool it may be sufficient as-is. + seth -- Seth Falcon | Computational Biology | Fred Hutchinson Cancer Research Center http://bioconductor.org ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
