Function from_str

src/parser.rs:99–137

Parse a flags value from text. This function will fail on any names that don't correspond to defined flags. Unknown bits will be retained. */

(input: &str)

Unknown bits will be retained.
*/
pub fn from_str<B: Flags>(input: &str) -> Result<B, ParseError>
where
    B::Bits: ParseHex,
{
    let mut parsed_flags = B::empty();

    // If the input is empty then return an empty set of flags
    if input.trim().is_empty() {
        return Ok(parsed_flags);
    }

    for flag in input.split('|') {
        let flag = flag.trim();

        // If the flag is empty then we've got missing input
        if flag.is_empty() {
            return Err(ParseError::empty_flag());
        }

        // If the flag starts with `0x` then it's a hex number
        // Parse it directly to the underlying bits type
        let parsed_flag = if let Some(flag) = flag.strip_prefix("0x") {
            let bits =
                <B::Bits>::parse_hex(flag).map_err(|_| ParseError::invalid_hex_flag(flag))?;

            B::from_bits_retain(bits)
        }
        // Otherwise the flag is a name
        // The generated flags type will determine whether
        // or not it's a valid identifier
        else {
            B::from_name(flag).ok_or_else(|| ParseError::invalid_named_flag(flag))?
        };

        parsed_flags.insert(parsed_flag);
    }

    Ok(parsed_flags)
}

/**
Write a flags value as text, ignoring any unknown bits.