How to get the name of the first argument in an assignment function?

If you are willing to write fu2[Var] <- 3 instead of fu2(Var) <- 3
then this workaround may suffice:

fu2 <- structure(NA, class = "fu2")
"[<-.fu2" <- function(x, ..., value) { print(match.call()[[3]]); fu2 }

# test
fu2[Var] <- 3  # prints "Var"

On 7/27/06, Heinz Tuechler <tuechler at gmx.at> wrote:

Dear All!

If I pass an object to an assignment function I cannot get it's name by
deparse(substitute(argument)), but I get *tmp* and I found no way to get
the original name, in the example below it should be "va1".
Is there a way?

Thanks,

Heinz

## example
'fu1<-' <- function(var, value) {
print(c(name.of.var=deparse(substitute(var))))}
fu1(va1) <- 3

name.of.var
   "*tmp*"

## desired result:
## name.of.var
##    "va1"



version
              _
platform       i386-pc-mingw32
arch           i386
os             mingw32
system         i386, mingw32
status         Patched
major          2
minor          3.1
year           2006
month          07
day            23
svn rev        38687
language       R
version.string Version 2.3.1 Patched (2006-07-23 r38687)