Rust unstable book: basic desc and example for `non_ascii_idents`.

diff --git a/src/doc/unstable-book/src/non-ascii-idents.md b/src/doc/unstable-book/src/non-ascii-idents.md
index f426022ab3a5161cc05a24b30912ad84605b7270..d5600c58fd9a657fff7c7e8c4c992335a2b4f666 100644 (file)
--- a/src/doc/unstable-book/src/non-ascii-idents.md
+++ b/src/doc/unstable-book/src/non-ascii-idents.md
@@ -6,5 +6,13 @@ The tracking issue for this feature is: [#28979]
 
 ------------------------
 
+The `non_ascii_idents` feature adds support for non-ASCII identifiers.
 
+## Examples
 
+```rust
+#![feature(non_ascii_idents)]
+
+const ε: f64 = 0.00001f64;
+const Π: f64 = 3.14f64;
+```
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