list of valid characters in object names
On Sat, Jul 27, 2013 at 3:08 PM, Duncan Murdoch
<murdoch.duncan at gmail.com> wrote:
Your question is a little ambiguous. All characters are allowed in object names, but the parser will only recognize some of them if they are quoted in backticks. The ones it recognizes without the backticks are ones that the C isalnum() (or iswalnum()) function declares to be alphanumeric, plus . and _. Your list above are all allowed, but locales are allowed to declare other characters to be alpha. I wouldn't recommend using anything else, because your code won't be recognized in other locales. The definitive reference for this is the source code, specifically src/main/gram.y. There's some discussion in the Intro to R manual, section 1.8.
Exactly what I was looking for. Thank you, Liviu