Hello, thank you for your response! In retrospect, though, I asked the wrong question--sorry about that. I should have asked, is there a good way to exclude white space from some parser (rather than lexer) rules, while ignoring it in others?
Essentially, I would like to pick apart the components of a string that excludes white space. Returning to the IPv4 address example, perhaps a more accurate version would be something like
ipAddress: byte1=INTEGER DOT byte2=INTEGER DOT byte3=INTEGER DOT byte4=INTEGER;
without allowing white space between the components of the address, while allowing it in other parser rules. I suppose I could use a lexer rule and pass its text through a regular expression afterward to pull out the parts, but it seems strange to resort to a separate regular expression when I'm already using an LL parser. (The text in my actual problem is more complex than an IP address, so I can't just split the string on dots.)