#![allow(dead_code, deprecated, unused_variables, unused_mut)]
use core::pin::Pin;
use core::mem::MaybeUninit;
struct PinArena<T> {
    memory: Box<[MaybeUninit<T>]>,
    len: usize,
}
impl<T> PinArena<T> {
    pub fn capacity(&self) -> usize {
        self.memory.len()
    }
    pub fn push(&mut self, val: T) -> Pin<&mut T> {
        if self.len >= self.capacity() {
            panic!("Attempted to push to a full pin arena!");
        }
        let ref_ = self.memory[self.len].write(val);
        self.len += 1;
        unsafe { Pin::new_unchecked(ref_) }
    }
}
fn main() {}