findGlobals must be explicitly ignoring calls to the ~ function. You could poke through the source code of codetools and find where this is happening.
Or, if you have the source code for the package you are investigating, use sed to change all "~" to "%TILDE%" and then use findGlobals on the resulting source code. The messages will be a bit garbled but should give you a start. E.g., compare the following two, in which y is defined in the function but x is not: > findGlobals(function(y)lm(y~x)) [1] "~" "lm" > findGlobals(function(y)lm(y %TILDE% x)) [1] "lm" "%TILDE%" "x" You will get false alarms, since in a call like lm(y~x+z, data=dat) findGlobals cannot know if dat includes columns called 'x', 'y', and 'z' and the above approach errs on the side of reporting the potential problem. You could use code in codetools to analyze S code instead of source code to globally replace all calls to "~" with calls to "%TILDE%" but that is more work than using sed on the source code. Bill Dunlap Spotfire, TIBCO Software wdunlap tibco.com > -----Original Message----- > From: [email protected] [mailto:[email protected]] On > Behalf > Of Hafen, Ryan P > Sent: Friday, November 02, 2012 4:28 PM > To: Bert Gunter > Cc: [email protected] > Subject: Re: [R] finding global variables in a function containing formulae > > Thanks. That works if I a have the formula expression handy. But suppose > I want a function, findGlobalVars() that takes a function as an argument > and finds globals in it, where I have absolutely no idea what is in the > supplied function: > > findGlobalVars <- function(f) { > require(codetools) > findGlobals(f, merge=FALSE)$variables > } > > > findGlobalVars(plotFn1) > > I would like findGlobalVars() to be able to find variables in formulae > that might be present in f. > > > > > On 11/1/12 1:19 PM, "Bert Gunter" <[email protected]> wrote: > > >Does > > > >?all.vars > >##as in > >> all.vars(y~x) > >[1] "y" "x" > > > >help? > > > >-- Bert > > > >On Thu, Nov 1, 2012 at 11:04 AM, Hafen, Ryan P <[email protected]> > >wrote: > >> I need to find all global variables being used in a function and > >>findGlobals() in the codetools package works quite nicely. However, I > >>am not able to find variables that are used in formulae. Simply > >>avoiding formulae in functions is not an option because I do not have > >>control over what functions this will be applied to. > >> > >> Here is an example to illustrate: > >> > >> library(codetools) > >> > >> xGlobal <- rnorm(10) > >> yGlobal <- rnorm(10) > >> > >> plotFn1 <- function() { > >> plot(yGlobal ~ xGlobal) > >> } > >> > >> plotFn2 <- function() { > >> y <- yGlobal > >> x <- xGlobal > >> plot(y ~ x) > >> } > >> > >> plotFn3 <- function() { > >> plot(xGlobal, yGlobal) > >> } > >> > >> findGlobals(plotFn1, merge=FALSE)$variables > >> # character(0) > >> findGlobals(plotFn2, merge=FALSE)$variables > >> # [1] "xGlobal" "yGlobal" > >> findGlobals(plotFn3, merge=FALSE)$variables > >> # [1] "xGlobal" "yGlobal" > >> > >> I would like to find that plotFn1 also uses globals xGlobal and > >>yGlobal. Any suggestions on how I might do this? > >> > >> ______________________________________________ > >> [email protected] 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. > > > > > > > >-- > > > >Bert Gunter > >Genentech Nonclinical Biostatistics > > > >Internal Contact Info: > >Phone: 467-7374 > >Website: > >http://pharmadevelopment.roche.com/index/pdb/pdb-functional-groups/pdb-bio > >statistics/pdb-ncb-home.htm > > ______________________________________________ > [email protected] 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. ______________________________________________ [email protected] 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.
