Hi Nim community! I am a new user of Nim language. It's very fun to program with.
To know Nim better, I am creating a mini GUI for fun. I am currently facing a problem that I can not solve .. I wish I could fill a sequence of widgets with different types (Layout, Button, ..) but with a common parent (Widget). I try the following in the [documentation](https://nim-lang.org/docs/manual.html#type-relations-covariance) but I do not understand the function of the keyword "out". When I try the documentation code I get an error that I do not understand: "The out modifier can be used only with imported types" So, I'm blocked with the following code: (I would like to make the commented code work) type Widget* = object of RootObj Layout* = ref object of Widget widgets*: seq[ref Widget] # widgets*: seq[ref Button] Button* = ref object of Widget proc newLayout(): ref Layout = new result result[] = new Layout result.widgets = @[] proc newButton(): ref Button = new result result[] = new Button proc addWidget(layout: ref Layout, widget: ref Widget) = # proc addWidget(layout: ref Layout, widget: ref Button) = layout.widgets.add widget var layout0 = newLayout() button0 = newButton() layout0.addWidget button0 Do you know if it is possible and how to match a type compared to that of his parent?
