Hi Bill, Thanks. According to the output, the assignment was triggered immediately after 'delayedAssign'. So strange.
> msg <- "old" > delayedAssign("x", { cat("Assigning 'msg' to 'x' now\n") ; msg }) > msg <- "new!" > x Assigning 'msg' to 'x' now [1] "new!" > msg <- "old" > delayedAssign("x", { cat("Assigning 'msg' to 'x' now\n") ; msg }) Assigning 'msg' to 'x' now > msg <- "new!" > x [1] "old" Best, Gang 2013/8/16 William Dunlap <wdun...@tibco.com> > Change > delayedAssign("x", msg) > to > delayedAssign("x", { cat("Assigning 'msg' to 'x' now\n") ; msg }) > and you will see the message when the delayed assignment is triggered. > You could add print(sys.calls()) to that to see the call stack if it isn't > obvious. > > > msg <- "old" > > delayedAssign("x", { cat("Assigning 'msg' to 'x' now\n") ; > print(sys.calls()) ; msg }) > > f <- function(p) paste(x, p) > > f("qwerty") > Assigning 'msg' to 'x' now > [[1]] > f("qwerty") > > [[2]] > paste(x, p) > > [[3]] > print(sys.calls()) > > [1] "old qwerty" > > x > [1] "old" > > > Bill Dunlap > Spotfire, TIBCO Software > wdunlap tibco.com > > > > -----Original Message----- > > From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] > On Behalf > > Of Gang Peng > > Sent: Wednesday, August 14, 2013 6:12 PM > > To: r-help@r-project.org > > Subject: [R] A question about using delayedAssign > > > > I run the examples in delayedAssign: > > > > msg <- "old" > > delayedAssign("x", msg) > > msg <- "new!" > > x > > > > If I run these four commands together, x is "new". If I run the first two > > commands first and then run the last two commands, x is "old". > > > > I just cannot figure out why. > > > > Thanks. > > Gang > > > > [[alternative HTML version deleted]] > > > > ______________________________________________ > > 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. > [[alternative HTML version deleted]] ______________________________________________ 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.