scheduler code cleanup

src/scheduler.rs

@@ -61,45 +61,56 @@ pub fn scheduler_mut<T>(lua:&mlua::Lua,mut f:impl FnMut(&mut crate::scheduler::S
 	let mut scheduler=lua.app_data_mut::<crate::scheduler::Scheduler>().ok_or(mlua::Error::runtime("Scheduler missing"))?;
 	f(&mut *scheduler)
 }
+
+fn schedule_thread(lua:&mlua::Lua,dt:mlua::Value)->Result<(),mlua::Error>{
+	let delay=match dt{
+		mlua::Value::Integer(i)=>i.max(0) as u64*60,
+		mlua::Value::Number(f)=>{
+			let delay=f.max(0.0)*60.0;
+			match delay.classify(){
+				std::num::FpCategory::Nan=>Err(mlua::Error::runtime("NaN"))?,
+				// cases where the number is too large to schedule
+				std::num::FpCategory::Infinite=>return Ok(()),
+				std::num::FpCategory::Normal=>if (u64::MAX as f64)<delay{
+					return Ok(());
+				},
+				_=>(),
+			}
+			delay as u64
+		},
+		mlua::Value::Nil=>0,
+		_=>Err(mlua::Error::runtime("Expected float"))?,
+	};
+	scheduler_mut(lua,|scheduler|{
+		scheduler.schedule_thread(delay.max(2),lua.current_thread());
+		Ok(())
+	})
+}
+
+// This is used to avoid calling coroutine.yield from the rust side.
+const LUA_WAIT:&str=
+"local coroutine_yield=coroutine.yield
+local schedule_thread=schedule_thread
+return function(dt)
+	schedule_thread(dt)
+	return coroutine_yield()
+end";
+
 pub fn set_globals(lua:&mlua::Lua,globals:&mlua::Table)->Result<(),mlua::Error>{
-	let schedule_thread=lua.create_function(|lua,dt:mlua::Value|{
-		let delay=match dt{
-			mlua::Value::Integer(i)=>i.max(0) as u64*60,
-			mlua::Value::Number(f)=>{
-				let delay=f.max(0.0)*60.0;
-				match delay.classify(){
-					std::num::FpCategory::Nan=>Err(mlua::Error::runtime("NaN"))?,
-					// cases where the number is too large to schedule
-					std::num::FpCategory::Infinite=>return Ok(()),
-					std::num::FpCategory::Normal=>if (u64::MAX as f64)<delay{
-						return Ok(());
-					},
-					_=>(),
-				}
-				delay as u64
-			},
-			mlua::Value::Nil=>0,
-			_=>Err(mlua::Error::runtime("Expected float"))?,
-		};
-		scheduler_mut(lua,|scheduler|{
-			scheduler.schedule_thread(delay.max(2),lua.current_thread());
-			Ok(())
-		})
-	})?;
+	let coroutine_table=globals.get::<mlua::Table>("coroutine")?;
+	let schedule_thread=lua.create_function(schedule_thread)?;
+
+	//create wait function environment
 	let wait_env=lua.create_table()?;
-	wait_env.raw_set("coroutine",globals.get::<mlua::Table>("coroutine")?)?;
+	wait_env.raw_set("coroutine",coroutine_table)?;
 	wait_env.raw_set("schedule_thread",schedule_thread)?;
-	let wait=lua.load("
-		local coroutine_yield=coroutine.yield
-		local schedule_thread=schedule_thread
-		return function(dt)
-			schedule_thread(dt)
-			return coroutine_yield()
-		end
-	")
+
+	//construct wait function from Lua code
+	let wait=lua.load(LUA_WAIT)
 	.set_name("wait")
 	.set_environment(wait_env)
 	.call::<mlua::Function>(())?;
+
 	globals.raw_set("wait",wait)?;
 
 	Ok(())