Dear R Users, Using codetools I obtained the text representation of the parse tree for this snippet
z=quote({x[1]<-2}) showTree(z) > ("{" (<- ([ x 1) 2)) (A) If I understand correctly, x[1]<-2 ought to be "[<-"(x,1,2), so shouldn't i see ("{" ( [<- x 1 2 ) ) If indeed the parse tree in (A) is correct, the operation ([ x 1) returns the value of x[1], how then does the <- operator know to change the 1st element of x ? Does the <- implementation inspect the its 1st argument (e.g if it sees [ call, it instead changes itself to implementation of "[<-"? Thank you Saptarshi ______________________________________________ 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.