Add more withXXX wrappers (#82)

- withStyleColor
- withStyleVar
- withIndent
- withItemWidth

Closes #63

src/DearImGui.hs

@@ -64,8 +64,11 @@ module DearImGui
   , Raw.endChild
 
     -- * Parameter stacks
+  , withStyleColor
   , pushStyleColor
   , Raw.popStyleColor
+
+  , withStyleVar
   , pushStyleVar
   , popStyleVar
 
@@ -75,9 +78,13 @@ module DearImGui
   , Raw.newLine
   , Raw.spacing
   , dummy
+
+  , withIndent
   , indent
   , unindent
+
   , setNextItemWidth
+  , withItemWidth
   , pushItemWidth
   , Raw.popItemWidth
 
@@ -1420,6 +1427,9 @@ dummy sizeRef = liftIO do
   size' <- get sizeRef
   with size' Raw.dummy
 
+withIndent :: MonadUnliftIO m => Float -> m a -> m a
+withIndent width =
+  bracket_ (indent width) (unindent width)
 
 -- | Move content position toward the right, by indent_w, or style.IndentSpacing if indent_w <= 0
 --
@@ -1445,6 +1455,10 @@ setNextItemWidth itemWidth = liftIO do
   Raw.setNextItemWidth (CFloat itemWidth)
 
 
+withItemWidth :: MonadUnliftIO m => Float -> m a -> m a
+withItemWidth width =
+  bracket_ (pushItemWidth width) Raw.popItemWidth
+
 -- Wraps @ImGui::PushItemWidth()@
 pushItemWidth :: (MonadIO m) => Float -> m ()
 pushItemWidth itemWidth = liftIO do
@@ -1504,7 +1518,13 @@ instance ToID (Ptr CChar, Int) where
 instance ToID String where
   pushID s = liftIO $ withCStringLen s pushID
 
--- | Modify a style color by pushing to the shared stack. always use this if you modify the style after `newFrame`
+withStyleColor :: (MonadUnliftIO m, HasGetter ref ImVec4) => ImGuiCol -> ref -> m a -> m a
+withStyleColor color ref =
+  bracket_ (pushStyleColor color ref) (Raw.popStyleColor 1)
+
+-- | Modify a style color by pushing to the shared stack.
+--
+-- Always use this if you modify the style after `newFrame`.
 --
 -- Wraps @ImGui::PushStyleColor()@
 pushStyleColor :: (MonadIO m, HasGetter ref ImVec4) => ImGuiCol -> ref -> m ()
@@ -1513,8 +1533,13 @@ pushStyleColor col colorRef = liftIO do
   with color \colorPtr ->
     Raw.pushStyleColor col colorPtr
 
+withStyleVar :: (MonadUnliftIO m, HasGetter ref ImVec2) => ImGuiStyleVar -> ref -> m a -> m a
+withStyleVar style ref =
+  bracket_ (pushStyleVar style ref) (Raw.popStyleVar 1)
 
--- | Modify a style variable by pushing to the shared stack. always use this if you modify the style after `newFrame`
+-- | Modify a style variable by pushing to the shared stack.
+--
+-- Always use this if you modify the style after `newFrame`.
 --
 -- Wraps @ImGui::PushStyleVar()@
 pushStyleVar :: (MonadIO m, HasGetter ref ImVec2) => ImGuiStyleVar -> ref -> m ()
@@ -1523,7 +1548,6 @@ pushStyleVar style valRef = liftIO do
   with val \valPtr ->
     Raw.pushStyleVar style valPtr
 
-
 -- | Remove style variable modifications from the shared stack
 --
 -- Wraps @ImGui::PopStyleVar()@