#![allow(dead_code, deprecated, unused_variables, unused_mut)]
use std::fmt;
struct Arm<'a, L, R>(&'a (L, R));
struct Table<'a, K, V>(&'a [(K, V)], V);
impl<'a, L, R> fmt::Debug for Arm<'a, L, R>
where
    L: 'a + fmt::Debug,
    R: 'a + fmt::Debug,
{
    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
        L::fmt(&(self.0).0, fmt)?;
        fmt.write_str(" => ")?;
        R::fmt(&(self.0).1, fmt)
    }
}
impl<'a, K, V> fmt::Debug for Table<'a, K, V>
where
    K: 'a + fmt::Debug,
    V: 'a + fmt::Debug,
{
    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
        fmt.debug_set()
            .entries(self.0.iter().map(Arm))
            .entry(&Arm(&(format_args!("_"), &self.1)))
            .finish()
    }
}
fn main() {}