Polish object interface (#138)

examples/doc_spriteScope.hs

@@ -0,0 +1,19 @@
+#!/usr/bin/env stack
+-- stack runghc --package reanimate
+module Main(main) where
+
+import Reanimate
+import Reanimate.Builtin.Documentation
+
+main :: IO ()
+main = reanimate $ docEnv $ sceneAnimation $ do
+  -- the rect lives through the entire 3s animation
+  newSpriteSVG_ $ translate (-3) 0 $ mkRect 4 4
+  wait 1
+  spriteScope $ do
+    -- the circle only lives for 1 second.
+    local <- newSpriteSVG $ translate 3 0 $ mkCircle 2
+    spriteE local $ overBeginning 0.3 fadeInE
+    spriteE local $ overEnding 0.3 fadeOutE
+    wait 1
+  wait 1