Improve the documentation for `rvalue_static_promotion`

3 files changed, 20 insertions, 2 deletions

diff --git a/src/doc/unstable-book/src/rvalue-static-promotion.md b/src/doc/unstable-book/src/rvalue-static-promotion.md
index 3b654960c8e..2583d350ebe 100644
--- a/src/doc/unstable-book/src/rvalue-static-promotion.md
+++ b/src/doc/unstable-book/src/rvalue-static-promotion.md
@@ -2,4 +2,22 @@
 
 The tracking issue for this feature is: [#38865]
 
+[#38865]: https://github.com/rust-lang/rust/issues/38865
+
 ------------------------
+
+The `rvalue_static_promotion` feature allows directly creating `'static` references to
+constant `rvalue`s, which in particular allowing for more concise code in the common case
+in which a `'static` reference is all that's needed.
+
+
+## Examples
+
+```rust
+#![feature(rvalue_static_promotion)]
+
+fn main() {
+    let DEFAULT_VALUE: &'static u32 = &42;
+    assert_eq!(*DEFAULT_VALUE, 42);
+}
+```
diff --git a/src/test/compile-fail/feature-gate-rvalue_static_promotion.rs b/src/test/compile-fail/feature-gate-rvalue_static_promotion.rs
index 41dc282be41..f33d0a71481 100644
--- a/src/test/compile-fail/feature-gate-rvalue_static_promotion.rs
+++ b/src/test/compile-fail/feature-gate-rvalue_static_promotion.rs
@@ -12,4 +12,4 @@
 fn main() {
     let x: &'static u32 = &42; //~ error: does not live long enough
     let y: &'static Option<u32> = &None; //~ error: does not live long enough
-}
\ No newline at end of file
+}
diff --git a/src/test/run-pass/rvalue-static-promotion.rs b/src/test/run-pass/rvalue-static-promotion.rs
index f8d93783877..30643cfc3eb 100644
--- a/src/test/run-pass/rvalue-static-promotion.rs
+++ b/src/test/run-pass/rvalue-static-promotion.rs
@@ -14,4 +14,4 @@
 fn main() {
     let x: &'static u32 = &42;
     let y: &'static Option<u32> = &None;
-}
\ No newline at end of file
+}