Constant ROMAN_NUMERAL_REGEX 

pub const ROMAN_NUMERAL_REGEX: &str;

! We need a regex that matches roman numerals but not the empty string, without using lookahead assertions that aren’t supported by hyperscan. We don’t want to match roman numerals ‘v’, ‘l’, or ‘c’, or numerals over 200, or uppercase, as these are usually false positives (see https://github.com/freelawproject/eyecite/issues/56 ). Match roman numerals 1 to 199 except for 5, 50, 100: