Constant lexical_util::format::HASKELL_STRING

pub const HASKELL_STRING: u128 = NumberFormatBuilder::new()
    .required_digits(true)
    .no_positive_mantissa_sign(true)
    .case_sensitive_special(true)
    .build(); // 202_824_096_036_516_704_239_472_512_862_239u128

Number format to parse a Haskell float from string.