#enum GtkPolicyType
#Determines when a scroll bar will be visible.
#@https://developer.gnome.org/gtk3/3.2/gtk3-Standard-Enumerations.html#GtkPolicyType
extern class GtkPolicyType `{GtkPolicyType`}
	#The scrollbar is always visible.
	new always `{ return GTK_POLICY_ALWAYS; `}

	#The scrollbar will appear and disappear as necessary.
	new automatic `{ return GTK_POLICY_AUTOMATIC; `}

	#The scrollbar will never appear.
	new never `{ return GTK_POLICY_NEVER; `}
end