v0.2.2

src/examples/_5_late_resources.rs

@@ -0,0 +1,91 @@
+//! Demonstrates initialization of resources in `init`.
+//!
+//! ```
+//! 
+//! #![deny(unsafe_code)]
+//! #![feature(proc_macro)]
+//! #![no_std]
+//! 
+//! extern crate cortex_m_rtfm as rtfm;
+//! extern crate stm32f103xx;
+//! 
+//! use rtfm::{app, Threshold};
+//! 
+//! app! {
+//!     device: stm32f103xx,
+//! 
+//!     resources: {
+//!         // Usually, resources are initialized with a constant initializer:
+//!         static ON: bool = false;
+//! 
+//!         // However, there are cases where this is not possible or not desired.
+//!         // For example, there may not be a sensible value to use, or the type may
+//!         // not be constructible in a constant (like `Vec`).
+//!         //
+//!         // While it is possible to use an `Option` in some cases, that requires
+//!         // you to properly initialize it and `.unwrap()` it at every use. It
+//!         // also consumes more memory.
+//!         //
+//!         // To solve this, it is possible to defer initialization of resources to
+//!         // `init` by omitting the initializer. Doing that will require `init` to
+//!         // return the values of all "late" resources.
+//!         static IP_ADDRESS: u32;
+//! 
+//!         // PORT is used by 2 tasks, making it a shared resource. This just tests
+//!         // another internal code path and is not important for the example.
+//!         static PORT: u16;
+//!     },
+//! 
+//!     idle: {
+//!         // Test that late resources can be used in idle
+//!         resources: [IP_ADDRESS],
+//!     },
+//! 
+//!     tasks: {
+//!         SYS_TICK: {
+//!             priority: 1,
+//!             path: sys_tick,
+//!             resources: [IP_ADDRESS, PORT, ON],
+//!         },
+//! 
+//!         EXTI0: {
+//!             priority: 2,
+//!             path: exti0,
+//!             resources: [PORT],
+//!         }
+//!     }
+//! }
+//! 
+//! // The signature of `init` is now required to have a specific return type.
+//! fn init(_p: init::Peripherals, _r: init::Resources) -> init::LateResourceValues {
+//!     // `init::Resources` does not contain `IP_ADDRESS`, since it is not yet
+//!     // initialized.
+//!     //_r.IP_ADDRESS;     // doesn't compile
+//! 
+//!     // ...obtain value for IP_ADDRESS from EEPROM/DHCP...
+//!     let ip_address = 0x7f000001;
+//! 
+//!     init::LateResourceValues {
+//!         // This struct will contain fields for all resources with omitted
+//!         // initializers.
+//!         IP_ADDRESS: ip_address,
+//!         PORT: 0,
+//!     }
+//! }
+//! 
+//! fn sys_tick(_t: &mut Threshold, r: SYS_TICK::Resources) {
+//!     // Other tasks can access late resources like any other, since they are
+//!     // guaranteed to be initialized when tasks are run.
+//! 
+//!     r.IP_ADDRESS;
+//! }
+//! 
+//! fn exti0(_t: &mut Threshold, _r: EXTI0::Resources) {}
+//! 
+//! fn idle(_t: &mut Threshold, _r: idle::Resources) -> ! {
+//!     loop {
+//!         rtfm::wfi();
+//!     }
+//! }
+//! ```
+// Auto-generated. Do not modify.

src/examples/mod.rs

@@ -5,5 +5,6 @@ pub mod _1_one_task;
 pub mod _2_two_tasks;
 pub mod _3_preemption;
 pub mod _4_nested;
-pub mod _5_generics;
-pub mod _6_full_syntax;
+pub mod _5_late_resources;
+pub mod _6_generics;
+pub mod _7_full_syntax;