Hi Ben (and everyone else), as this did not attract attention yet, let me start
>>>>> Ben Bolker <bbol...@gmail.com> >>>>> on Mon, 4 Jul 2016 11:49:40 -0400 writes: > Does anyone know if there's a reason that proc.time() uses cat() > rather than message() to print the output when there has been an error > in the process of timing? This is really not about proc.time(), but about system.time() [ and I have corrected the 'Subject' accordingly ] .. > line 31 of time.R, > https://github.com/wch/r-source/blob/e5b21d0397c607883ff25cca379687b86933d730/src/library/base/R/time.R#L31 > on.exit(cat("Timing stopped at:", ppt(proc.time() - time), "\n")) > This means that as far as I can tell the general way to make sure > there is no output from a timed statement is ... > tt1 <- capture.output(tt0 <- suppressMessages(suppressWarnings( > try(<stuff to try>, silent=TRUE)))) > (I know I could/should be using tryCatch() instead of try(), but I don't > think it really matters here ... ?) > What would people think of a request to change this to message() > rather than cat() in the future ... ? (This would mess up code that is > already using capture.output() to store this information ...) [I think that (last issue) would be acceptable.] One reason of the current cat() may just be historical: message() did not exist yet when system.time() was created. However, I agree that that is not good enough a reason to keep it. Much more important is the fact that it is *nice* that the message Timing stopped at: ... is printed in many cases when a system.time()d call is stopped early. Quite often for me this is *not* when an error happens as your suppress*() contortions (;-) suggest, but rather when I interrupt the long lasting call. And the current setup nicely gives > i <- 0; system.time( while(TRUE) i <- i+1 ) C-c C-c Timing stopped at: 1.001 0.084 1.086 > However, at least this simple case, also works fine with message() instead of cat() ... as I just tried now. A harder case are the "bad errors", e.g., memory overflow and similar bad things... cat() seems to be pretty robust, where as message() does invoke a handler (exactly *why* you want it, right?) and that may be harder to keep working correctly after certain errors than a simple cat(). I hope that some real experts (on "context switching", "long jumps", etc) would chime in now. Martin ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel