Add a configuration guide for edition
@@ -2065,6 +2065,22 @@ ignore = [
]
```
+## `edition`
+
+Specifies which edition is used by the parser.
+
+- **Default value**: `Edition2015`
+- **Possible values**: `Edition2015`, `Edition2018`
+- **Stable**: No
+
+### Example
+
+If you want to format code that requires edition 2018, add the following to your config file:
+
+```toml
+edition = "Edition2018"
+```
+
## `emit_mode`
Internal option
