Qt 4.5 to be LGPL

[Yigal Chripun]

Eldar Insafutdinov wrote:
> Yigal Chripun Wrote:
>
>> Bill Baxter wrote:
>>> On Fri, Jan 16, 2009 at 10:22 AM, Walter Bright
>>> <newshound1 at digitalmars.com>   wrote:
>>>> Bill Baxter wrote:
>>>>> On Fri, Jan 16, 2009 at 9:00 AM, Yigal
>>>>> Chripun<yigal100 at gmail.com>   wrote:
>>>>>
>>>>>> 2. there's more to S&S than just an array of delegates -
>>>>>> they are weak refs so that destruction of an object
>>>>>> disconnects automatically the apropriate signals. but there
>>>>>> is a weakref lib for D written by Bill IIRC, that could be
>>>>>> utilized in qtD. no pre-processor needed.
>>>>> The "delegates" in Qt are more like a QObject,QString pair.
>>>>> The object and the *name* of the method to call.
>>>>>
>>>>> And there aren't really "weak refs" in Qt.  When you connect
>>>>> a signal and slot it also makes some extra connections
>>>>> between the two objects' destroyed() signals.  So each object
>>>>> is also listening for the other object to be destroyed.
>>>>> Sort of a weak ref, but more like a strong ref with active
>>>>> notifications about destruction either way.   In a GC'ed
>>>>> language with real weak refs, the slot holder doesn't have
>>>>> to worry if the signal sender disappears.
>>>> This is taken care of in std.signals.
>>> WeakRef Yigal was referring to is just a handy wrapper class for
>>> the same GC callback that std.signals uses.  Plus it's compatible
>>> with both Phobos and Tango.
>>>
>>> --bb
>> What I meant was that QT provides the functionality of a weakref,
>> but you're right that that's not a "real" weak ref. still, I think
>> this functionality need to be implemented in qtD and luckily D does
>> have true weakrefs that can be utilized for this.
>>
>> Question: since D2 now uses the same runtime as tango and that
>> includes the (same) GC, do we still need the wrapper, for D2 code?
>
> What do you mean by wrapper? Or you mean extern C++ capabilites of
> D2? I tried them, and they seem really poor. Besides nobody who I was
> asking knows when D2 finally stabilise and goes out of beta, tango
> for example isn't going to be ported to D2 in nearest future.

I was refering to Bill's WeakRef class. In the above quote you can see 
that he said: "WeakRef Yigal was referring to is just a handy wrapper 
class for the same GC callback that std.signals uses.  Plus it's 
compatible with both Phobos and Tango."