[Haskell-cafe] Help understanding this type

[Guru Devanla]

Hello Haskell-Cafe,

I have been recently studying the XMonad code and some related types
available in the X11 bindings library.

I came across this type:

newtype XEvent = XEvent XEventPtr

type XEventPtr = Ptr
<http://hackage.haskell.org/package/base-4.10.1.0/docs/Foreign-Ptr.html#t:Ptr>
XEvent
<http://hackage.haskell.org/package/X11-1.9/docs/Graphics-X11-Xlib-Event.html#t:XEvent>

Available here:
http://hackage.haskell.org/package/X11-1.9/docs/Graphics-X11-Xlib-Event.html#t:XEvent

It seems that this type is circular here. how does one use this type? Is it
possible to create a value out of this type? What is the use of this type?

Please could someone help me wrap my head around this?

Thanks
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