add example

Cargo.toml

@@ -175,6 +175,11 @@ name = "ecs_ruby"
 path = "examples/ruby/ecs.rs"
 required-features = ["ruby"]
 
+[[example]]
+name = "entity_variable_ruby"
+path = "examples/ruby/entity_variable.rs"
+required-features = ["ruby"]
+
 [dev-dependencies]
 tracing-subscriber = "0.3.18"
 mlua = { version = "0.9.8", features = ["luajit", "vendored", "send"] }

assets/examples/ruby/entity_variable.rb

@@ -0,0 +1,2 @@
+# Bevy::Entity.current can be used to access the entity that is currently being processed
+puts("Current entity index: #{Bevy::Entity.current.index}")

examples/ruby/entity_variable.rs

@@ -0,0 +1,17 @@
+use bevy::prelude::*;
+use bevy_scriptum::runtimes::ruby::prelude::*;
+use bevy_scriptum::{prelude::*, BuildScriptingRuntime};
+
+fn main() {
+    App::new()
+        .add_plugins(DefaultPlugins)
+        .add_scripting::<RubyRuntime>(|_| {})
+        .add_systems(Startup, startup)
+        .run();
+}
+
+fn startup(mut commands: Commands, assets_server: Res<AssetServer>) {
+    commands.spawn(Script::<RubyScript>::new(
+        assets_server.load("examples/ruby/entity_variable.rb"),
+    ));
+}