Crate pages

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An owned, heap-backed, dynamically-sized data page comprising a user-chosen header and data array packed into a single allocation. It is an owned object and the internal representation is a [NonNull].

§Example

use pages::Page;
use core::mem::MaybeUninit;
// A really crappy replacement for Box<Option<usize>>
struct Maybe(Page::<bool, usize>);
impl Maybe {
    fn new() -> Self { Maybe(Page::new(false, 1)) }
    fn put(&mut self, value: usize) {
        *self.0.header_mut() = true; // occupied
        unsafe { self.0.data().write(MaybeUninit::new(value)) };
    }
    fn get(&mut self) -> Option<usize> {
        if !(*self.0.header()) { return None; }
        *self.0.header_mut() = false; // free
        Some(unsafe { self.0.data().read().assume_init() })
    }
}

let mut maybe = Maybe::new();
assert_eq!(maybe.get(), None);
maybe.put(42);
assert_eq!(maybe.get(), Some(42));

Structs§

  • An owned, heap-backed, dynamically-sized data page comprising a user-chosen header and data array packed into a single allocation. It is an owned object and the internal representation is a [NonNull].
  • Describes the memory layout for a Page.
  • A mutable pointer to a dynamically-sized heap-backed data page comprising a user-chosen header and data array packed into a single allocation. The internal representation is a NonNull.