Module arc_swap::docs

Additional documentation.

Here we have some more general topics that might be good to know that just don’t fit to the crate level intro.

Also, there were some previous blog posts about the crate which you might find interesting.

Atomic orderings

Each operation on the ArcSwapAny with DefaultStrategy type callable concurrently (eg. load, but not into_inner) contains at least one SeqCst atomic read-write operation, therefore even operations on different instances have a defined global order of operations.

Features

The weak feature adds the ability to use arc-swap with the Weak pointer too, through the ArcSwapWeak type. The needed std support is stabilized in rust version 1.45 (as of now in beta).

The experimental-strategies enables few more strategies that can be used. Note that these are not part of the API stability guarantees and they may be changed, renamed or removed at any time.

The experimental-thread-local feature can be used to build arc-swap for no_std targets, by replacing occurences of std::thread_local! with the #[thread_local] directive. This requires a nightly Rust compiler as it makes use of the experimental thread_local feature. Using this features, thread-local variables are compiled using LLVM built-ins, which have several underlying modes of operation. To add support for thread-local variables on a platform that does not have OS or linker support, the easiest way is to use -Ztls-model=emulated and to implement __emutls_get_address by hand, as in this example from Clang.

Minimal compiler version

The 1 versions will compile on all compilers supporting the 2018 edition. Note that this applies only if no additional feature flags are enabled and does not apply to compiling or running tests.

Modules

• internal
  Internal details.
• limitations
  Limitations and common pitfalls.
• patterns
  Common use patterns
• performance
  Performance characteristics.