From 76e234599f6da0b7ee21b98da80201a3984ee323 Mon Sep 17 00:00:00 2001
From: Emil Fresk <emil.fresk@gmail.com>
Date: Thu, 7 Nov 2019 14:12:16 +0100
Subject: [PATCH] Added struct de-structure-ing example in tips & tricks

---
 book/en/src/by-example/tips.md |  9 +++++++
 examples/destructure.rs        | 47 ++++++++++++++++++++++++++++++++++
 2 files changed, 56 insertions(+)
 create mode 100644 examples/destructure.rs

diff --git a/book/en/src/by-example/tips.md b/book/en/src/by-example/tips.md
index a0082060a9..b923ed0850 100644
--- a/book/en/src/by-example/tips.md
+++ b/book/en/src/by-example/tips.md
@@ -165,3 +165,12 @@ crate and print the output to the console.
 $ # produces the same output as before
 $ cargo expand --example smallest | tail
 ```
+
+## Resource de-structure-ing
+
+When having a task taking multiple resources it can help in readability to split
+up the resource struct. Here're two examples on how this can be done:
+
+``` rust
+{{#include ../../../../examples/destructure.rs}}
+```
diff --git a/examples/destructure.rs b/examples/destructure.rs
new file mode 100644
index 0000000000..0cc3c1f1c2
--- /dev/null
+++ b/examples/destructure.rs
@@ -0,0 +1,47 @@
+//! examples/destructure.rs
+
+#![deny(unsafe_code)]
+#![deny(warnings)]
+#![no_main]
+#![no_std]
+
+use cortex_m_semihosting::hprintln;
+use lm3s6965::Interrupt;
+use panic_semihosting as _;
+
+#[rtfm::app(device = lm3s6965)]
+const APP: () = {
+    struct Resources {
+        // Some resources to work with
+        #[init(0)]
+        a: u32,
+        #[init(0)]
+        b: u32,
+        #[init(0)]
+        c: u32,
+    }
+
+    #[init]
+    fn init(_: init::Context) {
+        rtfm::pend(Interrupt::UART0);
+        rtfm::pend(Interrupt::UART1);
+    }
+
+    // Direct destructure
+    #[task(binds = UART0, resources = [a, b, c])]
+    fn uart0(cx: uart0::Context) {
+        let a = cx.resources.a;
+        let b = cx.resources.b;
+        let c = cx.resources.c;
+
+        hprintln!("UART0: a = {}, b = {}, c = {}", a, b, c).unwrap();
+    }
+
+    // De-structure-ing syntax
+    #[task(binds = UART1, resources = [a, b, c])]
+    fn uart1(cx: uart1::Context) {
+        let uart1::Resources { a, b, c } = cx.resources;
+
+        hprintln!("UART0: a = {}, b = {}, c = {}", a, b, c).unwrap();
+    }
+};