I wouldn't count on any way of capturing this thing being reliable in the long term. As I recall what I do in codetools and the compiler is use features of missing() to test for it, but try to abstract those uses into one or two places only so I can easily change them if missing()'s behavior changes. Basically this internal thing _shouldn't_ be visible at R level, and if we ever figure out how to make that happen it will.
Best, luke On Mon, 18 Feb 2013, Hadley Wickham wrote:
Hi all, I think there's a small buglet in quote: str(quote()) # Error in quote() : 0 arguments passed to 'quote' which requires 1 str(quote(expr = )) # symbol I bring this up because this seems like the most natural way of capturing the "missing" symbol with pure R code, compared to substitute() or bquote() or formals(plot)$x Hadley
-- Luke Tierney Chair, Statistics and Actuarial Science Ralph E. Wareham Professor of Mathematical Sciences University of Iowa Phone: 319-335-3386 Department of Statistics and Fax: 319-335-3017 Actuarial Science 241 Schaeffer Hall email: luke-tier...@uiowa.edu Iowa City, IA 52242 WWW: http://www.stat.uiowa.edu ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
