What should the return types of Lexeme::end() and Lexeme::len() be? about grmtools HOT 5 CLOSED

Should have been clear that I'm asking @ptersilie for thoughts.

from grmtools.

Does l.end().unwrap_or_else(|| l.start()) just return l.start(), which then makes &input[ return an empty string?

Maybe we can add a method l.was_inserted_by_error_recovery() that allows users to easily check if a lexeme is real or not. Or we add a function l.get_from_input(&input), which returns "" if the lexeme was inserted by error recovery, and then tell users to use that instead of indexing the input themselves?

from grmtools.

The inserted function allows you to tell if a lexeme was inserted by error recovery or not. My worry is that people will forget to test for that, then they'll do something like lexeme.end() and be surprised that they end up with a zero length lexeme (for a lexeme definition that seemingly could never be zero length). I'm just not sure if I'm being unduly paranoid or not.

from grmtools.

I think we can't reasonably worry about everything the user might forget, especially if that means we make the life of less forgetful users more difficult by forcing them to use workarounds like l.end().unwrap_or_else(|| l.start()). I rather have end/start return 0 if the lexeme was inserted. I'm sure users will quickly remember that these are inserted lexemes when they get zero length ones.

from grmtools.

OK, I'll raise a PR.

from grmtools.