Re: [Vala] Virtual methods in interfaces

[Abderrahim Kitouni <a kitouni gmail com>]

Hello,

                   في ج، 28-01-2011 عند 18:30 +1030 ، كتب James Moschou:
> But see this is just a workaround. What I want is for the subclass to
> inherit the interface and the interface implementation from the base
> class, and override certain aspects. But what you have to do instead
> is reimplement the interface, and override everything again. The two
> are the same thing in these examples because they are so trivial. But
> consider:
You almost got me with this one, but still I think I'm right :-p

You just found a bug in valac, but let's see your output. For the
subclass you got :

> subclass - virtual
> interface - other virtual
> Segmentation fault
here I get this instead (using the tip of switch-to-gir branch, which is
based on 0.11.3):


> subclass - virtual
> class - other virtual
> Segmentation fault
So the second one is correct (i.e. has probably been fixed meanwhile).
However, the third one still fails (the abstract interface method
implemented as non-virtual method). Using gdb, I found out that it is an
infinite recursion problem and commenting out the line :

iface->abstract_function = (void (*)(Interface*)) interface_abstract_function;

in the generated code makes it work as expected (i.e. I get "class -
abstract"). So you just have found a bug (rather 2, but one is already
fixed).

It might be a good idea to test all combinations of
abstract/virtual/implemented as virtual/normally implemented, etc. with
latest vala and report exactly what works and what doesn't.

HTH,
Abderrahim