Rather than using debug, I generally like using recover. When called, it shows the call stack, and you can pick what to view. Using option(error=recover) triggers it on errors. You can't step through code as when using browser(), but I find jumping to different points on the call stack to be more useful.
- Tom Tom Short EPRI Ross Boylan wrote: > > I would like to be able to trace execution into calls below the current > function, or to follow execution as calls return. This is roughly the > distinction between "step" and "next" in many debuggers. > > I would also like to be able to switch to a location further up the call > stack than the location at which I enter the debugger, to see the > context of the current operations. > > Are there ways to do these things with the R debugger? I've studied the > man pages and FAQ's, and looked at the debug package, but I don't see a > way except for manually calling debug on the function that is about to > be called if I want to descend. That's quite awkward, particularly > since it must be manually undone (the debug package may be better on > that score). I'm also not entirely sure that such recursion > (essentially, debugging within the debugger) is OK. > > I tried looking up the stack with things like sys.calls(), from within > the browser, but they operated as if I were at the top level (e.g., > sys.function(-1) gets an error that it can't go there). I was doing > this in ess, and there's some chance the "can't write .Last.value" error > (wording approximate) cause by having an old version is screwing things > up). > > Since R is interpreted I would expect debugging to be a snap, but these > limitations make me suspect there is something about the language design > that makes implementing these facilities hard. For example, the browser > as documented in the Green book has up and down functions to change the > frame (p. 265); these are conspicuously absent in R. > -- > Ross Boylan wk: (415) 514-8146 > 185 Berry St #5700 [EMAIL PROTECTED] > Dept of Epidemiology and Biostatistics fax: (415) 514-8150 > University of California, San Francisco > San Francisco, CA 94107-1739 hm: (415) 550-1062 > > ______________________________________________ > R-devel@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-devel > > -- View this message in context: http://www.nabble.com/Am-I-missing-something-about-debugging--tf2910389.html#a8134920 Sent from the R devel mailing list archive at Nabble.com. ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
