Include + for crates.io feature requirements

This change was introduced in commit 5f842f7 of rust-lang/crates.io.
rust-lang · Jul 27, 2020 · e8d4bbf · e8d4bbf
1 parent a93b317
commit e8d4bbf
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/src/doc/src/reference/features.md b/src/doc/src/reference/features.md
@@ -87,7 +87,7 @@ optional dependencies. This allows packages to internally enable/disable
 features without requiring a new dependency.
 
 > **Note**: [crates.io] requires feature names to only contain ASCII letters,
-> digits, `_`, or `-`.
+> digits, `_`, `-`, or `+`.
 
 ### Usage in end products