On Fri, Jul 2, 2010 at 9:27 AM, Jeffrey J. Hallman <jhall...@frb.gov> wrote: > Gabor Grothendieck <ggrothendi...@gmail.com> writes: >> Try this: >> >>> mx <- formals(identity)$x >>> missing(mx) >> [1] TRUE >>> sin(mx) >> Error in sin(mx) : 'mx' is missing > > Neat. There's no way to look at 'mx' because calling any function > with it as an argument gives that same error message, including the auto > print function. What exactly is 'mx' here?
You can't look at mx directly but you can look look at the expression that generates it to see that its a component of a pairlist with class "name" and type "symbol" : > class(formals(identity)) [1] "pairlist" > class(formals(identity)$x) [1] "name" > typeof(formals(identity)$x) [1] "symbol" ______________________________________________ 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.
