Refactor update pipelines

1 files changed, 6 insertions, 7 deletions

diff --git a/tween.scm b/tween.scm
index 3475a83..eb8fbd8 100644
--- a/tween.scm
+++ b/tween.scm
@@ -197,12 +197,11 @@
   ;; when the tween finishes.
 
   (define-pipeline (step-tweens tweens) (entity dt)
-    (let ((tw (entity-ref entity #:tween #f)))
-      (if (not tw)
-          entity
-          (receive (tw2 ent2) (tween-step tw entity dt)
-            (if (tween-finished? tw2)
-                (entity-set ent2 #:tween #f)
-                (entity-set ent2 #:tween tw2))))))
+      guard: (entity-ref entity #:tween #f)
+    (let ((tw (entity-ref entity #:tween)))
+      (receive (tw2 ent2) (tween-step tw entity dt)
+        (if (tween-finished? tw2)
+            (entity-set ent2 #:tween #f)
+            (entity-set ent2 #:tween tw2)))))
 
 ) ;; end module