# [−][src]Struct alloc::alloc::Global

    pub struct Global;

🔬 This is a nightly-only experimental API. (`allocator_api` #32838)

The global memory allocator.

This type implements the `Alloc` trait by forwarding calls to the allocator registered with the `#[global_allocator]` attribute if there is one, or the `std` crate’s default.

## Trait Implementations

###

`impl Debug for Global` | [src]

####

`fn fmt(&self, f: &mut Formatter) -> Result` | [src]

Formats the value using the given formatter. Read more

###

`impl Copy for Global` | [src]

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`impl Clone for Global` | [src]

####

`fn clone(&self) -> Global` | [src]

Returns a copy of the value. Read more

####

`fn clone_from(&mut self, source: &Self)` | 1.0.0 [src]

Performs copy-assignment from `source`. Read more

###

`impl Default for Global` | [src]

####

`fn default() -> Global` | [src]

Returns the "default value" for a type. Read more

###

`impl Alloc for Global` | [src]

####

`unsafe fn alloc(&mut self, layout: Layout) -> Result<NonNull<u8>, AllocErr>` | [src]

🔬 This is a nightly-only experimental API. (`allocator_api` #32838)

Returns a pointer meeting the size and alignment guarantees of `layout`. Read more

####

`unsafe fn dealloc(&mut self, ptr: NonNull<u8>, layout: Layout)` | [src]

🔬 This is a nightly-only experimental API. (`allocator_api` #32838)

Deallocate the memory referenced by `ptr`. Read more

####

`unsafe fn realloc( &mut self, ptr: NonNull<u8>, layout: Layout, new_size: usize ) -> Result<NonNull<u8>, AllocErr>` | [src]

🔬 This is a nightly-only experimental API. (`allocator_api` #32838)

Returns a pointer suitable for holding data described by a new layout with `layout`’s alignment and a size given by `new_size`. To accomplish this, this may extend or shrink the allocation referenced by `ptr` to fit the new layout. Read more

####

`unsafe fn alloc_zeroed( &mut self, layout: Layout ) -> Result<NonNull<u8>, AllocErr>` | [src]

🔬 This is a nightly-only experimental API. (`allocator_api` #32838)

Behaves like `alloc`, but also ensures that the contents are set to zero before being returned. Read more

####

`fn usable_size(&self, layout: &Layout) -> (usize, usize)` | [src]

🔬 This is a nightly-only experimental API. (`allocator_api` #32838)

Returns bounds on the guaranteed usable size of a successful allocation created with the specified `layout`. Read more

####

`unsafe fn alloc_excess(&mut self, layout: Layout) -> Result<Excess, AllocErr>` | [src]

🔬 This is a nightly-only experimental API. (`allocator_api` #32838)

Behaves like `alloc`, but also returns the whole size of the returned block. For some `layout` inputs, like arrays, this may include extra storage usable for additional data. Read more

####

`unsafe fn realloc_excess( &mut self, ptr: NonNull<u8>, layout: Layout, new_size: usize ) -> Result<Excess, AllocErr>` | [src]

🔬 This is a nightly-only experimental API. (`allocator_api` #32838)

Behaves like `realloc`, but also returns the whole size of the returned block. For some `layout` inputs, like arrays, this may include extra storage usable for additional data. Read more

####

`unsafe fn grow_in_place( &mut self, ptr: NonNull<u8>, layout: Layout, new_size: usize ) -> Result<(), CannotReallocInPlace>` | [src]

🔬 This is a nightly-only experimental API. (`allocator_api` #32838)

Attempts to extend the allocation referenced by `ptr` to fit `new_size`. Read more

####

`unsafe fn shrink_in_place( &mut self, ptr: NonNull<u8>, layout: Layout, new_size: usize ) -> Result<(), CannotReallocInPlace>` | [src]

🔬 This is a nightly-only experimental API. (`allocator_api` #32838)

Attempts to shrink the allocation referenced by `ptr` to fit `new_size`. Read more

####

`fn alloc_one<T>(&mut self) -> Result<NonNull<T>, AllocErr>` | [src]

🔬 This is a nightly-only experimental API. (`allocator_api` #32838)

Allocates a block suitable for holding an instance of `T`. Read more

####

`unsafe fn dealloc_one<T>(&mut self, ptr: NonNull<T>)` | [src]

🔬 This is a nightly-only experimental API. (`allocator_api` #32838)

Deallocates a block suitable for holding an instance of `T`. Read more

####

`fn alloc_array<T>(&mut self, n: usize) -> Result<NonNull<T>, AllocErr>` | [src]

🔬 This is a nightly-only experimental API. (`allocator_api` #32838)

Allocates a block suitable for holding `n` instances of `T`. Read more

####

`unsafe fn realloc_array<T>( &mut self, ptr: NonNull<T>, n_old: usize, n_new: usize ) -> Result<NonNull<T>, AllocErr>` | [src]

🔬 This is a nightly-only experimental API. (`allocator_api` #32838)

Reallocates a block previously suitable for holding `n_old` instances of `T`, returning a block suitable for holding `n_new` instances of `T`. Read more

####

`unsafe fn dealloc_array<T>( &mut self, ptr: NonNull<T>, n: usize ) -> Result<(), AllocErr>` | [src]

🔬 This is a nightly-only experimental API. (`allocator_api` #32838)

Deallocates a block suitable for holding `n` instances of `T`. Read more

## Auto Trait Implementations

###

`impl Send for Global` |

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`impl Sync for Global` |

## Blanket Implementations

###

`impl<T> ToOwned for T where T: Clone,` | [src]

#### `type Owned = T`

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`fn to_owned(&Self) -> T` | [src]

Creates owned data from borrowed data, usually by cloning. Read more

####

`fn clone_into(&Self, &mut T)` | [src]

🔬 This is a nightly-only experimental API. (`toowned_clone_into` #41263)

recently added

Uses borrowed data to replace owned data, usually by cloning. Read more

###

`impl<T> From for T` | [src]

####

`fn from(t: T) -> T` | [src]

Performs the conversion.

###

`impl<T, U> TryFrom for T where T: From<U>,` | [src]

#### `type Error = !`

🔬 This is a nightly-only experimental API. (`try_from` #33417)

The type returned in the event of a conversion error.

####

`fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>` | [src]

🔬 This is a nightly-only experimental API. (`try_from` #33417)

Performs the conversion.

###

`impl<T, U> TryInto for T where U: TryFrom<T>,` | [src]

#### `type Error = <U as TryFrom<T>>::Error`

🔬 This is a nightly-only experimental API. (`try_from` #33417)

The type returned in the event of a conversion error.

####

`fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>` | [src]

🔬 This is a nightly-only experimental API. (`try_from` #33417)

Performs the conversion.

###

`impl<T, U> Into for T where U: From<T>,` | [src]

####

`fn into(self) -> U` | [src]

Performs the conversion.

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`impl<T> Borrow for T where T: ?Sized,` | [src]

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`fn borrow(&self) -> &T` | [src]

Immutably borrows from an owned value. Read more

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`impl<T> BorrowMut for T where T: ?Sized,` | [src]

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`fn borrow_mut(&mut self) -> &mut T` | [src]

Mutably borrows from an owned value. Read more

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`impl<T> Any for T where T: 'static + ?Sized,` | [src]

####

`fn get_type_id(&self) -> TypeId` | [src]

🔬 This is a nightly-only experimental API. (`get_type_id` #27745)

this method will likely be replaced by an associated static

Gets the `TypeId` of `self`. Read more

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