Thank you. That answers my question. -- Bert
On Fri, Jun 7, 2013 at 7:09 AM, Prof Brian Ripley <rip...@stats.ox.ac.uk> wrote: > On 07/06/2013 14:49, Bert Gunter wrote: >> >> Folks: >> >> Feel free to provide me a link or reference instead of an answer. >> >> Preamble: >> >> f <- function() function(x)rnorm(x) >> g <- f() >> g(3) >> ## [1] -0.4448492 -0.2379978 -0.4537394 >> >> ## But >> rnorm <- function()1 ## nasty nasty >> g(3) >> ## Error in rnorm(x) : unused argument(s) (x) >> >> ## of course f <- function()function(x)stats:::rnorm(x) >> ## would fix this. >> >> Question 1: >> Suppose I defined f() as at top in a package namespace and exported it. >> Would a user see this same error defining g() and with rnorm redefined >> as above? (Assume stats is attached as usual). I presume so, but ... > > > Not if done right. The package should importFrom(stats, rnorm). > >> Question 2: >> If the answer to Q1 is yes, (how) can this be avoided without using fully >> qualified function names? >> >> Again, a quick reference to relevant docs would suffice. > > > 'Writing R Extensions' says > > 'The namespace controls the search strategy for variables used by functions > in the package. If not found locally, R searches the package namespace > first, then the imports, then the base namespace and then the normal search > path.' > > -- > Brian D. Ripley, rip...@stats.ox.ac.uk > Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ > University of Oxford, Tel: +44 1865 272861 (self) > 1 South Parks Road, +44 1865 272866 (PA) > Oxford OX1 3TG, UK Fax: +44 1865 272595 -- Bert Gunter Genentech Nonclinical Biostatistics Internal Contact Info: Phone: 467-7374 Website: http://pharmadevelopment.roche.com/index/pdb/pdb-functional-groups/pdb-biostatistics/pdb-ncb-home.htm ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.