Struct gharial::TestBox

pub struct TestBox<T, A>where
    A: GlobalAlloc,{ /* private fields */ }

TestBox behaves like std::boxed::Box except for it owns a reference to a GlobalAlloc .

If template parameter A is GAlloc , it causes assertion error if the instance is not dropped or dropped twice.

See also GBox , which is an alias to TestBox<T, GAlloc> .

For example, it sometimes requires to allocate heap memory to implement container struct, and then the elements must be dropped manually. This struct helps the test.

Implementations

impl<T, A> TestBox<T, A>where A: GlobalAlloc,

pub fn new(x: T, alloc: A) -> Self

Creates a new instance.

Examples

use gharial::{GAlloc, TestBox};

let alloc = GAlloc::default();
let _box = TestBox::new(5, alloc);

pub unsafe fn from_raw_alloc(ptr: *mut T, alloc: A) -> Self

Creates a new instance from raw pointer and a reference to allocator.

After calling this function, the raw pointer is owned by the resulting TestBox . Specifically, TestBox::drop destructs the referenced object and free the pointer.

Safety

To use this function safe, the ptr should be allocated via alloc and it should not be freed anywhere else.

Examples

use gharial::{GAlloc, TestBox};
use std::alloc::{handle_alloc_error, GlobalAlloc, Layout};

let alloc = GAlloc::default();
let ptr = unsafe {
    let layout = Layout::new::<i32>();
    let ptr = alloc.alloc(layout) as *mut i32;
    if ptr.is_null() {
        handle_alloc_error(layout);
    }

    *ptr = 5;
    ptr
};

let _box = unsafe { TestBox::from_raw_alloc(ptr, alloc) };

impl<T, A> TestBox<T, A>where A: GlobalAlloc,

pub fn leak<'a>(tb: Self) -> &'a mut Twhere T: 'a,

Consumes and leaks TestBox .

Examples

use gharial::{GAlloc, TestBox};

let alloc = GAlloc::default();

let five = TestBox::new(5, alloc.clone());
let leaked = TestBox::leak(five);
assert_eq!(5, *leaked);

let five_ = unsafe { TestBox::from_raw_alloc(leaked, alloc) };

pub fn into_raw(tb: Self) -> *mut T

Consumes the TestBox and returning a wrapped raw pointer.

Examples

use gharial::{GAlloc, TestBox};

let alloc = GAlloc::default();

let five = TestBox::new(5, alloc.clone());
let raw = TestBox::into_raw(five);
assert_eq!(5, unsafe { *raw });

let five_ = unsafe { TestBox::from_raw_alloc(raw, alloc) };

Trait Implementations

impl<T, A> AsMut<T> for TestBox<T, A>where A: GlobalAlloc,

fn as_mut(&mut self) -> &mut T

Converts this type into a mutable reference of the (usually inferred) input type.

impl<T, A> AsRef<T> for TestBox<T, A>where A: GlobalAlloc,

fn as_ref(&self) -> &T

Converts this type into a shared reference of the (usually inferred) input type.

impl<T, A> Borrow<T> for TestBox<T, A>where A: GlobalAlloc,

fn borrow(&self) -> &T

Immutably borrows from an owned value.

impl<T, A> BorrowMut<T> for TestBox<T, A>where A: GlobalAlloc,

fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value.

impl<T, A> Clone for TestBox<T, A>where T: Clone, A: Clone + GlobalAlloc,

fn clone(&self) -> Self

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T: Debug, A> Debug for TestBox<T, A>where A: GlobalAlloc + Debug,

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<T, A> Default for TestBox<T, A>where T: Default, A: Default + GlobalAlloc,

fn default() -> Self

Returns the “default value” for a type.

impl<T, A> Deref for TestBox<T, A>where A: GlobalAlloc,

type Target = T

The resulting type after dereferencing.

fn deref(&self) -> &T

Dereferences the value.

impl<T, A> DerefMut for TestBox<T, A>where A: GlobalAlloc,

fn deref_mut(&mut self) -> &mut T

Mutably dereferences the value.

impl<T, A> Drop for TestBox<T, A>where A: GlobalAlloc,

fn drop(&mut self)

Executes the destructor for this type.

impl<T, A> From<T> for TestBox<T, A>where A: Default + GlobalAlloc,

fn from(val: T) -> Self

Converts to this type from the input type.

impl<T, A> Hash for TestBox<T, A>where T: Hash, A: GlobalAlloc,

fn hash<H>(&self, state: &mut H)where H: Hasher,

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl<T, A> Ord for TestBox<T, A>where T: Ord, A: GlobalAlloc,

fn cmp(&self, rh: &Self) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Selfwhere Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Selfwhere Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Selfwhere Self: Sized + PartialOrd<Self>,

Restrict a value to a certain interval.

impl<T, A> PartialEq<TestBox<T, A>> for TestBox<T, A>where T: PartialEq, A: GlobalAlloc,

fn eq(&self, rh: &Self) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<T, A> PartialOrd<TestBox<T, A>> for TestBox<T, A>where T: PartialOrd, A: GlobalAlloc,

fn partial_cmp(&self, rh: &Self) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl<T, A> Eq for TestBox<T, A>where T: Eq, A: GlobalAlloc,