fn try_parse_r_dotname(tokens: &[TokenTree]) -> Option<String>Expand description
Try to parse a token sequence as an R dot-separated function name.
Accepts alternating Ident Punct('.') Ident Punct('.') … Ident (odd
number of tokens, starting and ending with Ident). Returns the
reconstructed name string (e.g. "is.null") or None.