const fn r1(c: char) -> Interval {
    Interval {
        first: c as u32,
        last: c as u32,
    }
}
/// Construct an interval from a single char.
Construct an interval from a single char.
Construct an interval from a single char .
const fn r1(c: char) -> Interval {
    Interval {
        first: c as u32,
        last: c as u32,
    }
}
const fn r1 ( c : char ) -> Interval { Interval { first : c as u32 , last : c as u32 , } }
Construct an interval from a single char.
Construct an interval from a single char .
c
char