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@ -28,7 +28,7 @@ For instance, a custom implementation of `Box` might write `Drop` like this:
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```rust
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```rust
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#![feature(ptr_internals, allocator_api)]
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#![feature(ptr_internals, allocator_api)]
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use std::alloc::{AllocRef, Global, GlobalAlloc, Layout};
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use std::alloc::{Allocator, Global, GlobalAlloc, Layout};
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use std::mem;
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use std::mem;
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use std::ptr::{drop_in_place, NonNull, Unique};
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use std::ptr::{drop_in_place, NonNull, Unique};
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@ -39,7 +39,7 @@ impl<T> Drop for Box<T> {
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unsafe {
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unsafe {
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drop_in_place(self.ptr.as_ptr());
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drop_in_place(self.ptr.as_ptr());
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let c: NonNull<T> = self.ptr.into();
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let c: NonNull<T> = self.ptr.into();
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Global.dealloc(c.cast(), Layout::new::<T>())
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Global.deallocate(c.cast(), Layout::new::<T>())
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}
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}
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}
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}
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}
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}
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@ -55,7 +55,7 @@ However this wouldn't work:
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```rust
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```rust
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#![feature(allocator_api, ptr_internals)]
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#![feature(allocator_api, ptr_internals)]
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use std::alloc::{AllocRef, Global, GlobalAlloc, Layout};
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use std::alloc::{Allocator, Global, GlobalAlloc, Layout};
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use std::ptr::{drop_in_place, Unique, NonNull};
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use std::ptr::{drop_in_place, Unique, NonNull};
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use std::mem;
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use std::mem;
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@ -66,7 +66,7 @@ impl<T> Drop for Box<T> {
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unsafe {
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unsafe {
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drop_in_place(self.ptr.as_ptr());
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drop_in_place(self.ptr.as_ptr());
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let c: NonNull<T> = self.ptr.into();
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let c: NonNull<T> = self.ptr.into();
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Global.dealloc(c.cast(), Layout::new::<T>());
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Global.deallocate(c.cast(), Layout::new::<T>());
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}
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}
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}
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}
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}
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}
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@ -79,7 +79,7 @@ impl<T> Drop for SuperBox<T> {
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// Hyper-optimized: deallocate the box's contents for it
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// Hyper-optimized: deallocate the box's contents for it
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// without `drop`ing the contents
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// without `drop`ing the contents
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let c: NonNull<T> = self.my_box.ptr.into();
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let c: NonNull<T> = self.my_box.ptr.into();
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Global.dealloc(c.cast::<u8>(), Layout::new::<T>());
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Global.deallocate(c.cast::<u8>(), Layout::new::<T>());
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}
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}
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}
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}
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}
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}
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@ -128,7 +128,7 @@ of Self during `drop` is to use an Option:
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```rust
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```rust
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#![feature(allocator_api, ptr_internals)]
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#![feature(allocator_api, ptr_internals)]
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use std::alloc::{AllocRef, GlobalAlloc, Global, Layout};
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use std::alloc::{Allocator, GlobalAlloc, Global, Layout};
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use std::ptr::{drop_in_place, Unique, NonNull};
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use std::ptr::{drop_in_place, Unique, NonNull};
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use std::mem;
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use std::mem;
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@ -139,7 +139,7 @@ impl<T> Drop for Box<T> {
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unsafe {
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unsafe {
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drop_in_place(self.ptr.as_ptr());
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drop_in_place(self.ptr.as_ptr());
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let c: NonNull<T> = self.ptr.into();
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let c: NonNull<T> = self.ptr.into();
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Global.dealloc(c.cast(), Layout::new::<T>());
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Global.deallocate(c.cast(), Layout::new::<T>());
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}
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}
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}
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}
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}
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}
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@ -154,7 +154,7 @@ impl<T> Drop for SuperBox<T> {
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// field as `None` to prevent Rust from trying to Drop it.
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// field as `None` to prevent Rust from trying to Drop it.
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let my_box = self.my_box.take().unwrap();
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let my_box = self.my_box.take().unwrap();
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let c: NonNull<T> = my_box.ptr.into();
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let c: NonNull<T> = my_box.ptr.into();
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Global.dealloc(c.cast(), Layout::new::<T>());
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Global.deallocate(c.cast(), Layout::new::<T>());
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mem::forget(my_box);
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mem::forget(my_box);
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}
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}
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}
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}
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