Google has posted a style guide for R which is being used throughout the organization. It's mostly in line with what I learned once upon a time, but it's nice to see such an authoritative body coming out with a set of standards. Universal coding benefits everyone, and R is growing so rapidly that some form of standardization is becoming necessary.
A couple bullets:
- File names: end in
variable.name, FunctionName, kConstantName
- Indentation: two spaces, no tabs
- Curly Braces: first on same line, last on own line
- Assignment: use
- Semicolons: don't use them
The full guide is available here.