please recommend an editor

Kevin,

  I am using R in Mac OS 10.3.8 and I am trying to find an editor  
which is compatible with R in Mac. I recently bumped into Xcode for  
a few times in Mac when I directly opened scripts. Would Xcode be a  
good editor to learn? Are there a lot people use it?

Xcode is nice, but the R support is limited to some syntax  
highlighting (which was posted on this list some time ago).  
Personally I use either the integrated editor in the R GUI or Emacs  
(Carbon Emacs 22.0.50 to be more precise). Both have good R  
integration (i.e. not just syntax highlighting, but also auto- 
completion of functions, objects and argument lookup). The integrated  
R GUI editor is more suitable for beginners, Emacs is ... well,  
Emacs :) powerful if you know how to use it (and it's the only one  
with Rd mode AFAIK). I have also heard that SubEthaEdit is a really  
good editor with R syntax highlighting support, but never used it  
myself.

Cheers,
Simon