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use crate::Formula;

#[derive(Debug)]
pub enum Error {}

impl std::fmt::Display for Error {
    fn fmt(&self, _: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        unreachable!("No variants exist for literals::Error")
    }
}

impl std::error::Error for Error {}

pub struct True;

impl<T> Formula<T> for True {
    type Error = Error;

    fn satisfied_by(&self, _value: &T) -> Result<bool, Self::Error> {
        Ok(true)
    }
}

pub struct False;

impl<T> Formula<T> for False {
    type Error = Error;

    fn satisfied_by(&self, _value: &T) -> Result<bool, Self::Error> {
        Ok(false)
    }
}