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//! Miscellaneous utility functions.
use smallvec::SmallVec;

pub mod cursor;
pub mod dataflow;

/// Move the lone item out of a 1-element container.
pub trait Lone<T> {
    fn lone(self) -> T;
}

impl<T> Lone<T> for T {
    fn lone(self) -> T {
        self
    }
}

impl<T> Lone<T> for Vec<T> {
    fn lone(mut self) -> T {
        assert!(self.len() == 1);
        self.pop().unwrap()
    }
}

impl<T> Lone<T> for SmallVec<[T; 1]> {
    fn lone(mut self) -> T {
        assert!(self.len() == 1);
        self.pop().unwrap()
    }
}