docs: Add docs on splitting yolk.rhai into multiple files

docs/src/yolk_rhai.md

@@ -102,3 +102,35 @@ To look at the contents of those variables or try out your logic, you can always
 ```bash
 $ yolk eval 'print(SYSTEM)'
 ```
+
+## Splitting up into multiple files
+
+Rhai allows you to import other files into your scripts.
+For example, let's say you want to keep your color theme definition in a separate file.
+Simply create a new `colors.rhai` file next to your `yolk.rhai`, and make sure to explicitly declare exported variables as `export`:
+
+```rust
+export let gruvbox = #{
+  background: "#282828",
+  foreground: "#ebdbb2",
+};
+
+fn some_function() {
+    print("hi")
+}
+```
+
+Note that functions are exported by default.
+
+Now, in your `yolk.rhai`, import this script, giving the module an explict name:
+
+```rs
+import "colors" as colors;
+```
+
+Now you can refer to anything exported from that file as `colors::thing`, i.e.:
+
+```rs
+let theme = colors::gruvbox;
+colors::some_function();
+```

src/script/stdlib.rs

@@ -110,10 +110,17 @@ pub fn utils_module() -> Module {
         .in_global_namespace()
         .set_into_module(&mut module, rhai_color_hex_to_rgb);
 
+    FuncRegistration::new("color_hex_to_rgb")
+        .with_comments(["/// Convert a hex color string to an RGB map."])
+        .with_params_info(["hex_string: &str", "Result<Map>"])
+        .in_global_namespace()
+        .set_into_module(&mut module, rhai_color_hex_to_rgb);
+
     let color_hex_to_rgb_str = |hex_string: String| -> Result<String, Box<EvalAltResult>> {
         let (r, g, b, _) = color_hex_to_rgb(&hex_string)?;
         Ok(format!("rgb({r}, {g}, {b})"))
     };
+
     FuncRegistration::new("color_hex_to_rgb_str")
         .with_comments(["/// Convert a hex color string to an RGB string."])
         .with_params_info(["hex_string: &str", "Result<String>"])