Allocator

Module std.memory

import std.memory;

Public declaration contracts and authored examples. A page can document several related symbols. Implementation bodies are excluded.

Allocator

pub concept Allocator<Self>

Defines the structural raw-storage protocol used by owning containers.

An allocator starts and ends allocation storage only; it never begins or ends a T object lifetime. Every operation is unsafe because callers own the exact identity, layout, lifetime, alias, and compatibility proofs.

Example

module example.allocator;
from std.memory import DefaultAllocator, Layout;
fn Main() -> i32 {
    var Heap = default(DefaultAllocator);
    let StorageLayout = Layout.Of<u64>();
    unsafe {
        switch Heap.Allocate(StorageLayout) {
            case .Ok { Value = Storage } => {
                Heap.Free(Storage, StorageLayout);
                return 0;
            }
            case .Err { Error = _ } => return 1;
        }
    }
}

Allocator.Allocate

requires unsafe fn Allocate(StorageLayout: Layout)
        -> Result<mut byte*, AllocationError>;

Acquires one distinct nonnull allocation identity. StorageLayout: Exact valid requested layout. Return: Writable raw bytes or a recoverable allocation error.

Allocator.Free

requires unsafe fn Free(
        Storage: mut byte*,
        StorageLayout: Layout
    ) -> void;

Releases one compatible allocation without destroying objects. Storage: Exact base pointer, or null only with default(Layout). StorageLayout: Exact layout used to acquire nonnull storage. Return: No value after the allocation lifetime ends.