For this application I would use names(formals(object)) to extract the formal arguments.
luke On Mon, 7 Feb 2011, William Dunlap wrote:
I was looking for all the glm-related 'family' functions in stats using the following predicate that returns TRUE for any function whose first argument is called "link". is.family <- function(object) is.function(object) && identical(names(as.list(object))[1], "link") It threw an error when applied to SSfol > is.family(SSfol) Error in as.vector(x, "list") : cannot coerce type 'closure' to vector of type 'list' but works when I unclass SSfol > is.family(unclass(SSfol)) [1] FALSE It looks like as.list fails on any function that is assigned a class: > as.list(function(x)x+1) $x [[2]] x + 1 > as.list(structure(function(x)x+1, class="unrecognized class name")) Error in as.vector(x, "list") : cannot coerce type 'closure' to vector of type 'list' Bill Dunlap Spotfire, TIBCO Software wdunlap tibco.com ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
-- Luke Tierney 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: l...@stat.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