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use crate::Error;
/// Version number for PSI table syntax section.
#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, PartialOrd, Ord)]
pub struct VersionNumber(u8);
impl VersionNumber {
/// Maximum version number.
pub const MAX: u8 = (1 << 5) - 1;
/// Makes a new `VersionNumber` instance that has the value `0`.
pub fn new() -> Self {
VersionNumber(0)
}
/// Makes a new `VersionNumber` instance with the given value.
///
/// # Errors
///
/// If `n` exceeds `VersionNumber::MAX`, it will return an `ErrorKind::InvalidInput` error.
pub fn from_u8(n: u8) -> Result<Self, Error> {
assert!(n <= Self::MAX, "Too large version number: {}", n);
Ok(VersionNumber(n))
}
/// Returns the value of the version number.
pub fn as_u8(&self) -> u8 {
self.0
}
/// Increments the version number.
///
/// It will be wrapped around if overflow.
pub fn increment(&mut self) {
self.0 = (self.0 + 1) & Self::MAX;
}
}
impl Default for VersionNumber {
fn default() -> Self {
Self::new()
}
}