remove instances of 'local ... in ... end', replacing it with opauque structures with signatures, because I like the lower indentation level and additional whitespace in the latter

functional-core/app-init.sml

@@ -1,44 +1,51 @@
-structure AppInit =
+signature APP_INIT = 
+sig
+  val fromWidthAndHeight : int * int -> AppType.app_type
+end
+
+structure AppInit :> APP_INIT =
 struct
   open AppType
 
-  local
-    fun init (windowWidth, windowHeight, wStart, wFinish, hStart, hFinish) =
+  fun helpFromWidthAndHeight
+    (windowWidth, windowHeight, wStart, wFinish, hStart, hFinish) =
+    let
+      val xClickPoints = ClickPoints.generate (wStart, wFinish)
+      val yClickPoints = ClickPoints.generate (hStart, hFinish)
+      val graphLines =
+        GraphLines.generate
+          (windowWidth, windowHeight, xClickPoints, yClickPoints)
+    in
+      { triangles = []
+      , triangleStage = NO_TRIANGLE
+      , windowWidth = windowWidth
+      , windowHeight = windowHeight
+      , xClickPoints = xClickPoints
+      , yClickPoints = yClickPoints
+      , graphLines = graphLines
+      }
+    end
+
+  fun fromWidthAndHeight (windowWidth, windowHeight) =
+    if windowWidth = windowHeight then
+      helpFromWidthAndHeight
+        (windowWidth, windowHeight, 0, windowWidth, 0, windowHeight)
+    else if windowWidth > windowHeight then
       let
-        val xClickPoints = ClickPoints.generate (wStart, wFinish)
-        val yClickPoints = ClickPoints.generate (hStart, hFinish)
-        val graphLines =
-          GraphLines.generate
-            (windowWidth, windowHeight, xClickPoints, yClickPoints)
+        val difference = windowWidth - windowHeight
+        val wStart = difference div 2
+        val wFinish = wStart + windowHeight
       in
-        { triangles = []
-        , triangleStage = NO_TRIANGLE
-        , windowWidth = windowWidth
-        , windowHeight = windowHeight
-        , xClickPoints = xClickPoints
-        , yClickPoints = yClickPoints
-        , graphLines = graphLines
-        }
+        helpFromWidthAndHeight
+          (windowWidth, windowHeight, wStart, wFinish, 0, windowHeight)
+      end
+    else
+      let
+        val difference = windowHeight - windowWidth
+        val hStart = difference div 2
+        val hFinish = hStart + windowWidth
+      in
+        helpFromWidthAndHeight
+          (windowWidth, windowHeight, 0, windowWidth, hStart, hFinish)
       end
-  in
-    fun fromWidthAndHeight (windowWidth, windowHeight) =
-      if windowWidth = windowHeight then
-        init (windowWidth, windowHeight, 0, windowWidth, 0, windowHeight)
-      else if windowWidth > windowHeight then
-        let
-          val difference = windowWidth - windowHeight
-          val wStart = difference div 2
-          val wFinish = wStart + windowHeight
-        in
-          init (windowWidth, windowHeight, wStart, wFinish, 0, windowHeight)
-        end
-      else
-        let
-          val difference = windowHeight - windowWidth
-          val hStart = difference div 2
-          val hFinish = hStart + windowWidth
-        in
-          init (windowWidth, windowHeight, 0, windowWidth, hStart, hFinish)
-        end
-  end
 end