[R] local and global variables

[n.vialma at libero.it]

Hi all,
I have a question about global and local variables.First of all, a variable 
defined in a for loop is it a local or global variable??
Second, I'm trying to build a loop in the following way:
I have these 3 data frames
bilanci_2005<-bilanci1[ANNO==2005,]
bilanci_2006<-bilanci1[ANNO==2006,]
bilanci_2007 <--bilanci1[ANNO==2007,]

LOOP:
v=list(2005,2006,2007)      
for (a in v){
anno1=a
anno2=a+1
for (i in 1:length(bilanci_a)) {
assign(paste(""bilanci",anno1,anno2,sep=""), rbind(paste("bilanci",anno1,anno2,
sep=""),
                          bilanci_anno2[bilanci_anno2$CFISCALE==bilanci_anno1
[i,]$CFISCALE,],
                          "bilanci_anno1[i,])
}
}
 what I'm trying to do is for example to give the contents of   a (so the 
values which are in the list named v) to the bilanci variable. In Stata this 
means using a particular kind of  "".
How can I do this in R?