R-help and Barry Thank you for your suggestions. It works, and may I ask how I am able to do the opposite (disable the call back, so that I could control when to show and suppress the output). I would like to make a function to enable/disable the callback similar to the one as follow:
enableOutput <- function() { h <<- taskCallbackManager() h$add(function(expr, value, ok, visible) {if(!visible){print(value)};TRUE}) } disableOutput <- function() { ........ } This shows output feature (and use '';" to suppress the output) is the default behavior of Matlab which I find it quite useful (without having to type in the variable name again every time to see the result of the expression). So I am just curious to know how to do it in R. Best Regards, Anthony On 31 July 2011 20:16, Barry Rowlingson <b.rowling...@lancaster.ac.uk> wrote: >> h <- taskCallbackManager() >> h$add(function(expr, value, ok, visible) {if(!visible){print(value)};TRUE}) > > > On Sun, Jul 31, 2011 at 12:15 PM, Anthony Ching Ho Ng > <anthony.ch...@gmail.com> wrote: >> Hello R-help, >> >> I wonder if it is possible to configure R, so that it will >> display/show the evaluation result of the R commands automatically >> (similar to the behavior of Matlab) >> >> i.e. If I type x <- 8 >> >> it will print 8 in the command prompt, instead of having type x >> explicitly to show the result and perhaps put an ";" at the end to >> suppress the output. >> >> i.e. x <- 8; >> > > The first thing I think you can do by adding a task callback manager > to print the value if the value would otherwise be invisible: > > > h <- taskCallbackManager() > > h$add(function(expr, value, ok, visible) {if(!visible){print(value)};TRUE}) > > The semicolon thing would probably need rewriting bits of R at the C > code level. > > I don't think many people would use it though. And my code above > might break things. I don't use it. > > Barry > ______________________________________________ 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.