>>>>> Dennis Fisher <fis...@plessthan.com> >>>>> on Thu, 22 Feb 2018 13:01:37 -0800 writes:
> Luke > Thanks — I revised the code to: > ERRORMESSAGE <- try(source(USERSCRIPTFILE, local=T), silent=T) > print(ERRORMESSAGE) now returns: > $value >  0 > $visible >  FALSE > Not clear what to make of that. > Dennis The help page ?try has contained for a long time ‘try’ is implemented using ‘tryCatch’; for programming, instead of ‘try(expr, silent = TRUE)’, something like ‘tryCatch(expr, error = function(e) e)’ (or other simple error handler functions) may be more efficient and flexible. and you do use 'silent=T' (which is "unsafe" (*) !) I'd strongly advocate you use the 2nd proposition by given by Luke Tierney (cited below): Learn to use tryCatch() instead of try() and then such things can be done considerably less obscurely. Best, Martin Maechler, ETH Zurich -- *) Using 'T' instead of 'TRUE' (of 'F' instead of 'FALSE' *is* unsafe): a previous 'T <- 0' will change what you really wanted. TRUE and FALSE are "constants" in R, whereas T and F are variables > Dennis Fisher MD > P < (The "P Less Than" Company) > Phone / Fax: 1-866-PLessThan (1-866-753-7784) > www.PLessThan.com >> On Feb 22, 2018, at 12:45 PM, luke-tier...@uiowa.edu wrote: >> >> Only the default error handler puts the error message in a buffer >> where it can be retrieved with geterrmessage. try() replaces the >> default error handler. Either look at the value returned by try() or >> use tryCatch with conditionMessage. >> >> Best, >> >> luke >> >> On Thu, 22 Feb 2018, Dennis Fisher wrote: >> >>> R 3.4.3 >>> OS X >>> >>> Colleagues >>> >>> I have a 20K line script in which I encounter an unexpected problem. >>> >>> If the script detects presence of a particular file USERCODE.txt, it executes: >>> source(“USERCODE.txt”) >>> If that file is not present, the script executes without a problem. >>> >>> There might be syntax errors in USERCODE.txt; therefore, the code above is embedded in a try command: >>> try(source(“USERCODE.txt", local=T), silent=T) >>> followed by: >>> ERRORMESSAGE <- geterrmessage() >>> >>> For unclear reasons, an earlier command is yielding an error message: >>> unused argument (\"\\n\") >>> Despite identifying the exact source of that error, I can’t fix it (and it is of no consequence). >>> >>> Ideally, I would like to clear out the pre-existing error message immediately before the “try” command (or perhaps at that particular location where it is being created) — but I can’t figure out how to do so. >>> >>> Any suggestions would be welcome. >>> >>> Dennis >>> >>> Dennis Fisher MD >>> P < (The "P Less Than" Company) >>> Phone / Fax: 1-866-PLessThan (1-866-753-7784) >>> www.PLessThan.com >>> >>> ______________________________________________ >>> Remail@example.com mailing list -- To UNSUBSCRIBE and more, see >>> 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. >>> >> >> -- >> Luke Tierney >> Ralph E. Wareham Professor of Mathematical Sciences >> University of Iowa Phone: 319-335-3386 >> Department of Statistics and Fax: 319-335-3017 >> Actuarial Science >> 241 Schaeffer Hall email: luke-tier...@uiowa.edu >> Iowa City, IA 52242 WWW: http://www.stat.uiowa.edu > ______________________________________________ > Rfirstname.lastname@example.org mailing list -- To UNSUBSCRIBE and more, see > 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. ______________________________________________ Remail@example.com mailing list -- To UNSUBSCRIBE and more, see 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.