using ``<-'' in function argument
Le 12/3/2010 11:35, Berwin A Turlach a ?crit :
G'day Ivan, On Fri, 03 Dec 2010 10:54:58 +0100 Ivan Calandra<ivan.calandra at uni-hamburg.de> wrote:
Arf, yes it makes sense now!
Well, my original post said: "R has lazy evaluation" and "the assignment takes place when the function evaluates the argument" :)
Well you did say it indeed... but it doesn't mean that I understood it, I needed more details to grasp it!
So the idea here is: never use "<-" in function argument...
Never say never. :) But if you want to perform a (global) assignment within an actual argument to a function, you should better be sure that the formal argument gets evaluated. In fact, this trick is probably a good way, short of studying the source, to find out whether an argument gets evaluated or not (or only occasionally). Cheers, Berwin
Ivan CALANDRA PhD Student University of Hamburg Biozentrum Grindel und Zoologisches Museum Abt. S?ugetiere Martin-Luther-King-Platz 3 D-20146 Hamburg, GERMANY +49(0)40 42838 6231 ivan.calandra at uni-hamburg.de ********** http://www.for771.uni-bonn.de http://webapp5.rrz.uni-hamburg.de/mammals/eng/1525_8_1.php