'Implements' not being enforced unless used

Monkey Forums/Monkey Programming/'Implements' not being enforced unless used

AaronK

(Posted 2012) [#1]

Hi all. I have just noticed that even if a class says it implements an interface, you can happy NOT implement it and the compiler does not care, so long as you don't call it. While it doesn't generate errors per-se it does mean that typos can go unnoticed and as you continue development you may find yourself having to debug a strange error down the track when you actually do use it.

Here's an example:

Interface I
Method Do()
End

Class C Implements I
Method Do(i:Int) ' Note the Int here
End
End

' This takes an actual C so all good
Function GoAndDo(c:C)
c.Do(20)
End

Function Main()
Local c:C = New C()
GoAndDo(c)
End

This all works fine, but it is a little inconsistent with what Interface implies I think. An error to tell you about unimplemented interface methods would be nice.

Cheers
Aaron

AaronK

(Posted 2012) [#2]

An extension to this problem seems to be with globals. If I have

Global thingy:SomeClass = new SomeClass()

class SomeClass
Method New()
DoSomeInitisation()
End
end

Then New() isn't called when the program starts. Is this expected behaviour?

I use this way of working quite a lot in C++. The object gets created, and registers itself with some sort of other object in the constructor.

dopeyrulz

(Posted 2012) [#3]

Aaron,

As you point out only the code that is actually referred to is processed. I believe Mark outlined the reasons for this at some stage.

AaronK

(Posted 2012) [#4]

Hi Matt, thanks for that. Looks like I'll need to be a bit more careful then but it'd still be a nice addition I think.