add example

Cargo.toml

@@ -170,6 +170,10 @@ name = "custom_type_ruby"
 path = "examples/ruby/custom_type.rs"
 required-features = ["ruby"]
 
+[[example]]
+name = "ecs_ruby"
+path = "examples/ruby/ecs.rs"
+required-features = ["ruby"]
 
 [dev-dependencies]
 tracing-subscriber = "0.3.18"

assets/examples/ruby/ecs.rb

@@ -0,0 +1 @@
+print_player_names

examples/ruby/ecs.rs

@@ -0,0 +1,33 @@
+use bevy::prelude::*;
+use bevy_scriptum::prelude::*;
+use bevy_scriptum::runtimes::ruby::prelude::*;
+
+#[derive(Component)]
+struct Player;
+
+fn main() {
+    App::new()
+        .add_plugins(DefaultPlugins)
+        .add_scripting::<RubyRuntime>(|runtime| {
+            runtime.add_function(
+                String::from("print_player_names"),
+                |players: Query<&Name, With<Player>>| {
+                    for player in &players {
+                        println!("player name: {}", player);
+                    }
+                },
+            );
+        })
+        .add_systems(Startup, startup)
+        .run();
+}
+
+fn startup(mut commands: Commands, assets_server: Res<AssetServer>) {
+    commands.spawn((Player, Name::new("John")));
+    commands.spawn((Player, Name::new("Mary")));
+    commands.spawn((Player, Name::new("Alice")));
+
+    commands.spawn(Script::<RubyScript>::new(
+        assets_server.load("examples/ruby/ecs.rb"),
+    ));
+}