Expand description
§The Rust core allocation and collections library
This library provides smart pointers and collections for managing heap-allocated values.
This library, like core, normally doesn’t need to be used directly
since its contents are re-exported in the std
crate.
Crates that use the #![no_std]
attribute however will typically
not depend on std
, so they’d use this crate instead.
§Boxed values
The Box
type is a smart pointer type. There can only be one owner of a
Box
, and the owner can decide to mutate the contents, which live on the
heap.
This type can be sent among threads efficiently as the size of a Box
value
is the same as that of a pointer. Tree-like data structures are often built
with boxes because each node often has only one owner, the parent.
§Reference counted pointers
The Rc
type is a non-threadsafe reference-counted pointer type intended
for sharing memory within a thread. An Rc
pointer wraps a type, T
, and
only allows access to &T
, a shared reference.
This type is useful when inherited mutability (such as using Box
) is too
constraining for an application, and is often paired with the Cell
or
RefCell
types in order to allow mutation.
§Atomically reference counted pointers
The Arc
type is the threadsafe equivalent of the Rc
type. It
provides all the same functionality of Rc
, except it requires that the
contained type T
is shareable. Additionally, Arc<T>
is itself
sendable while Rc<T>
is not.
This type allows for shared access to the contained data, and is often paired with synchronization primitives such as mutexes to allow mutation of shared resources.
§Collections
Implementations of the most common general purpose data structures are defined in this library. They are re-exported through the standard collections library.
§Heap interfaces
The alloc
module defines the low-level interface to the
default global allocator. It is not compatible with the libc allocator API.
Modules§
- Memory allocation APIs
- A module for working with borrowed data.
- The
Box<T>
type for heap allocation. - Collection types.
- Utilities for formatting and printing
String
s. - Utilities for the slice primitive type.
- Utilities for the
str
primitive type. - A UTF-8–encoded, growable string.
- A contiguous growable array type with heap-allocated contents, written
Vec<T>
.
Macros§
- Creates a
String
using interpolation of runtime expressions.