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Interface inheritance problem

Monkey Forums/Monkey Programming/Interface inheritance problem

itto(Posted 2014) [#1]
Hi guys, I'm having a hard time figuring out why the following code isn't working.

I have a base class which implements an interface, and a child class which extends the base class and implements its own interface. I need the interface implemented by the child class to extend the one implemented by the base class and use interfaces for variable types, but I can't manage to make it work.

Interface IFoo
	Method GetName:String()
End

Interface IBar Extends IFoo
	Method SetName(name:String)
End

Class Foo Implements IFoo
	
	Method GetName:String()
		Return name
	End
	
	Private Field name:String = "John Doe"
	
End

Class Bar Extends Foo Implements IBar

              ' without implementing this, the code doesn't work
	' Method GetName:String()
	' 	Return name
	' End
	Method SetName(name:String)
		Self.name = name
	End

End

Function Main()

	Local foo:IBar = New Bar()
	foo.SetName("Mister X")
	Print foo.GetName()
	
End



I get the following error: "Method IFoo.GetName:String() must be implemented by class Bar".

It looks like Bar is not extending Foo properly.


Goodlookinguy(Posted 2014) [#2]
What version of Monkey are you using and it looks like a bug. If you're using the latest experimental version and this fails, then report it.

Edit: A workaround for now would be
Class Bar Extends Foo Implements IBar

              ' without implementing this, the code doesn't work
	Method GetName:String()
		Return Super.GetName()
	End
	Method SetName(name:String)
		Self.name = name
	End

End



itto(Posted 2014) [#3]
What version of Monkey are you using


I'm using Monkey v77A and TRANS monkey compiler V1.39

The workaround is the same I found, but it's useless as it doesn't make sense to inherit from a base class if I have to rewrite each method every time for each subclass :(


Goodlookinguy(Posted 2014) [#4]
The way I see it right now is that the interface is inheriting a method that needs to be implemented by the class. It doesn't consider the extended class to have the method that the interface inherited, so it's failing. A little confusing sounding, but it makes sense why this bug would occur at least.

Definitely report this bug ASAP if someone hasn't already reported it. By the way, I just tried it in 78a and it failed.


itto(Posted 2014) [#5]
Thank you for your prompt support. I submitted a bug report, I hope it's something which can be fixed or solved somehow.
Meanwhile it would be great if someone could try this code with another monkey version.


Samah(Posted 2014) [#6]
This is essentially the same bug I reported last year:
http://monkey-x.com/Community/posts.php?topic=6160

Mark's official response was "I can fix it, but not yet".


muddy_shoes(Posted 2014) [#7]
As I posted in the bug report thread, the issue was reported back in mid 2012 and got a "not right now" reply. This worse (because it's not flagged by Monkey) bug: http://www.monkeycoder.co.nz/Community/posts.php?topic=2878, in the same area, was reported around the same time, never even got a response, and appears to be still broken in 77d.

I wouldn't hold your breath.


Samah(Posted 2014) [#8]
Perhaps a nice person could fork trans on Github and fix it. I'd do it but it'd just be another excuse to not work on my game.