Merge pull request #528 from us-irs/docs-improvements

improvements for documentation

Author: newAM

src/lib.rs

@@ -43,28 +43,84 @@
 //!
 //! List of currently implemented data structures:
 #![cfg_attr(
-    any(arm_llsc, target_pointer_width = "32", target_pointer_width = "64"),
-    doc = "- [`Arc`](pool::arc::Arc) -- like `std::sync::Arc` but backed by a lock-free memory pool rather than `#[global_allocator]`"
+    any(
+        arm_llsc,
+        all(
+            target_pointer_width = "32",
+            any(target_has_atomic = "64", feature = "portable-atomic")
+        ),
+        all(
+            target_pointer_width = "64",
+            any(
+                all(target_has_atomic = "128", feature = "nightly"),
+                feature = "portable-atomic"
+            )
+        )
+    ),
+    doc = "- [Arc][pool::arc::Arc] -- like `std::sync::Arc` but backed by a lock-free memory pool rather than [global_allocator]"
+)]
+#![cfg_attr(
+    any(
+        arm_llsc,
+        all(
+            target_pointer_width = "32",
+            any(target_has_atomic = "64", feature = "portable-atomic")
+        ),
+        all(
+            target_pointer_width = "64",
+            any(
+                all(target_has_atomic = "128", feature = "nightly"),
+                feature = "portable-atomic"
+            )
+        )
+    ),
+    doc = "- [Box][pool::boxed::Box] -- like `std::boxed::Box` but backed by a lock-free memory pool rather than [global_allocator]"
 )]
 #![cfg_attr(
-    any(arm_llsc, target_pointer_width = "32", target_pointer_width = "64"),
-    doc = "- [`Box`](pool::boxed::Box) -- like `std::boxed::Box` but backed by a lock-free memory pool rather than `#[global_allocator]`"
+    any(
+        arm_llsc,
+        all(
+            target_pointer_width = "32",
+            any(target_has_atomic = "64", feature = "portable-atomic")
+        ),
+        all(
+            target_pointer_width = "64",
+            any(
+                all(target_has_atomic = "128", feature = "nightly"),
+                feature = "portable-atomic"
+            )
+        )
+    ),
+    doc = "- [Arc][pool::arc::Arc] -- like `std::sync::Arc` but backed by a lock-free memory pool rather than [global_allocator]"
 )]
-//! - [`BinaryHeap`] -- priority queue
-//! - [`Deque`] -- double-ended queue
-//! - [`HistoryBuffer`] -- similar to a write-only ring buffer
-//! - [`IndexMap`] -- hash table
-//! - [`IndexSet`] -- hash set
-//! - [`LinearMap`]
 #![cfg_attr(
-    any(arm_llsc, target_pointer_width = "32", target_pointer_width = "64"),
-    doc = "- [`Object`](pool::object::Object) -- objects managed by an object pool"
+    any(
+        arm_llsc,
+        all(
+            target_pointer_width = "32",
+            any(target_has_atomic = "64", feature = "portable-atomic")
+        ),
+        all(
+            target_pointer_width = "64",
+            any(
+                all(target_has_atomic = "128", feature = "nightly"),
+                feature = "portable-atomic"
+            )
+        )
+    ),
+    doc = "- [Object](pool::object::Object) -- objects managed by an object pool"
 )]
-//! - [`sorted_linked_list::SortedLinkedList`]
-//! - [`String`]
-//! - [`Vec`]
+//! - [BinaryHeap] -- priority queue
+//! - [Deque] -- double-ended queue
+//! - [HistoryBuffer] -- similar to a write-only ring buffer
+//! - [IndexMap] -- hash table
+//! - [IndexSet] -- hash set
+//! - [LinearMap]
+//! - [sorted_linked_list::SortedLinkedList]
+//! - [String]
+//! - [Vec]
 //! - [`mpmc::Q*`](mpmc) -- multiple producer multiple consumer lock-free queue
-//! - [`spsc::Queue`] -- single producer single consumer lock-free queue
+//! - [spsc] and [spsc::Queue] -- single producer single consumer lock-free queue
 //!
 //! # Minimum Supported Rust Version (MSRV)
 //!

src/spsc.rs

@@ -1,18 +1,18 @@
-//! A fixed capacity Single Producer Single Consumer (SPSC) queue.
+//! # A fixed capacity Single Producer Single Consumer (SPSC) queue.
 //!
 //! Implementation based on <https://www.codeproject.com/Articles/43510/Lock-Free-Single-Producer-Single-Consumer-Circular>
 //!
-//! # Portability
+//! ## Portability
 //!
 //! This module requires CAS atomic instructions which are not available on all architectures
 //! (e.g.  ARMv6-M (`thumbv6m-none-eabi`) and MSP430 (`msp430-none-elf`)). These atomics can be
 //! emulated however with [`portable-atomic`](https://crates.io/crates/portable-atomic), which is
 //! enabled with the `cas` feature and is enabled by default for `thumbv6m-none-eabi` and `riscv32`
 //! targets.
 //!
-//! # Examples
+//! ## Examples
 //!
-//! - `Queue` can be used as a plain queue
+//! - [Queue] can be used as a plain queue
 //!
 //! ```
 //! use heapless::spsc::Queue;
@@ -27,12 +27,16 @@
 //! assert_eq!(rb.dequeue(), Some(0));
 //! ```
 //!
-//! - `Queue` can be `split` and then be used in Single Producer Single Consumer mode.
+//! - [Queue] can be [Queue::split] and then be used in Single Producer Single Consumer mode.
 //!
 //! "no alloc" applications can create a `&'static mut` reference to a `Queue` -- using a static
 //! variable -- and then `split` it: this consumes the static reference. The resulting `Consumer`
 //! and `Producer` can then be moved into different execution contexts (threads, interrupt handlers,
-//! etc.)
+//! etc.).
+//!
+//! Alternatively, you can also create the Queue statically in the global scope by wrapping it with
+//! a [static_cell](https://docs.rs/static_cell/latest/static_cell/)
+//!
 //!
 //! ```
 //! use heapless::spsc::{Producer, Queue};
@@ -43,6 +47,8 @@
 //! }
 //!
 //! fn main() {
+//!     // Alternatively, use something like `static_cell` to create the `Queue` in the global
+//!     // scope.
 //!     let queue: &'static mut Queue<Event, 4> = {
 //!         static mut Q: Queue<Event, 4> = Queue::new();
 //!         unsafe { &mut Q }