Add note about including an external scanner in Rust crate
@@ -590,7 +590,7 @@ grammar({
});
```
-Then, add another C or C++ source file to your project. Currently, its path must be `src/scanner.c` or `src/scanner.cc` for the CLI to recognize it. Be sure to add this file to the `sources` section of your `binding.gyp` file so that it will be included when your project is compiled by Node.js.
+Then, add another C or C++ source file to your project. Currently, its path must be `src/scanner.c` or `src/scanner.cc` for the CLI to recognize it. Be sure to add this file to the `sources` section of your `binding.gyp` file so that it will be included when your project is compiled by Node.js and uncomment the appropriate block in your `bindings/rust/build.rs` file so that it will be included in your Rust crate.
In this new source file, define an [`enum`][enum] type containing the names of all of your external tokens. The ordering of this enum must match the order in your grammar's `externals` array.
