bit of cleanup, few steps towards commands demo

orchid-extension/src/system.rs

@@ -16,10 +16,10 @@ pub type ReqForSystem<T> = <CardForSystem<T> as SystemCard>::Req;
 /// System as defined by author
 pub trait System: Debug + 'static {
 	type Ctor: SystemCtor<Instance = Self>;
-	fn prelude(&self) -> impl Future<Output = Vec<Sym>>;
-	fn env(&self) -> impl Future<Output = Vec<GenMember>>;
-	fn lexers(&self) -> Vec<LexerObj>;
-	fn parsers(&self) -> Vec<ParserObj>;
+	fn prelude(&self) -> impl Future<Output = Vec<Sym>> { futures::future::ready(Vec::new()) }
+	fn env(&self) -> impl Future<Output = Vec<GenMember>> { futures::future::ready(Vec::new()) }
+	fn lexers(&self) -> Vec<LexerObj> { Vec::new() }
+	fn parsers(&self) -> Vec<ParserObj> { Vec::new() }
 	fn request<'a>(
 		&self,
 		hand: Box<dyn ReqHandle<'a> + 'a>,