1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
use core::fmt::{self, Display, Formatter}; #[cfg(feature = "std")] use std::error::Error; #[derive(Debug, Clone)] pub struct BooleanError; impl Display for BooleanError { #[inline] fn fmt(&self, f: &mut Formatter) -> Result<(), fmt::Error> { f.write_str("invalid boolean") } } #[cfg(feature = "std")] impl Error for BooleanError {}