If R is run in interactive mode; i.e., interactive() == TRUE, whatever function calls that produced R objects gets printed (by calling the appropriate print() method; known as auto-printing), unless the object is returned invisibly (i.e., wrapped in invisible()). As an example, if you put
abs(-3) into a file, then run that through R CMD BATCH, you will not see the output printed. Also, auto-printing is off inside loops; e.g., for (I in 1:10) abs(-3) will not show any output, even if you run it in an interactive session. Andy > From: xudongyuan > > Hi.All and R developers: > When I look into the R source code, I have a > question.Since R has its own data structure(i.e. SEXP),how > does it convert the result to the normal output after it has > computed? For example,when I input, > >abs(-3) > I learned that in R's execution, the expression is parsed to > a parse tree,and becomes a SEXP list. After "eval" function, > the result is still a SEXP. But R outputs: > [1] 3 > The output is normal.So my question is how R makes its SEXP > result into the normal result.Where can I find the place R > makes this convertion in R's source code?Can anyone help me? > thanks > > > dongyuan xu > > ______________________________________________ > [EMAIL PROTECTED] mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide! > http://www.R-project.org/posting-guide.html > > ______________________________________________ [EMAIL PROTECTED] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
