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digitalmars.D - Signals/Slots only with classes

reply Johann Lermer <johann.lermer elvin.eu> writes:
Hi everybody,

I'm just fiddling around with signals and slots and fell over 
this nasty bug:

(copied from std.signals)
"Slots can only be delegates formed from class objects or 
interfaces to class objects. If a delegate to something else is 
passed to connect(), such as a struct member function, a nested 
function, a COM interface or a closure, undefined behavior will 
result."

Is there any chance, that this bug is fixed in the near future 
ore is it something we have to live with?
Oct 17 2020
parent reply Basile B. <b2.temp gmx.com> writes:
On Saturday, 17 October 2020 at 16:22:39 UTC, Johann Lermer wrote:

 Hi everybody,

 I'm just fiddling around with signals and slots and fell over 
 this nasty bug:

 (copied from std.signals)
 "Slots can only be delegates formed from class objects or 
 interfaces to class objects. If a delegate to something else is 
 passed to connect(), such as a struct member function, a nested 
 function, a COM interface or a closure, undefined behavior will 
 result."

 Is there any chance, that this bug is fixed in the near future


No. std.signals is old, old-fashioned but is still there because 
there's no proposals to replace it and the standards for std are 
high.

std.signals is there not because it's good but rather for 
historiacal reasons.


 ore is it something we have to live with?


Likely. But you can work on something better and use it.
Oct 17 2020
next sibling parent Bastiaan Veelo <Bastiaan Veelo.net> writes:
On Saturday, 17 October 2020 at 16:36:37 UTC, Basile B. wrote:

 On Saturday, 17 October 2020 at 16:22:39 UTC, Johann Lermer 
 wrote:

 ore is it something we have to live with?


 Likely. But you can work on something better and use it.


There is https://code.dlang.org/packages/phobosx, but I have no 
experience with it.

Bastiaan.
Oct 17 2020
prev sibling parent reply Johann Lermer <johann.lermer elvin.eu> writes:
On Saturday, 17 October 2020 at 16:36:37 UTC, Basile B. wrote:

 No. std.signals is old, old-fashioned but is still there 
 because there's no proposals to replace it and the standards 
 for std are high.


Great. So there's a module in phobos that's not up to phobos' 
standards and it doesn't get improved, because the standards are 
too high. That's depressing.

Btw. why is it old-fashioned?
Oct 18 2020
parent reply norm <normical gmail.com> writes:
On Sunday, 18 October 2020 at 16:27:43 UTC, Johann Lermer wrote:

 On Saturday, 17 October 2020 at 16:36:37 UTC, Basile B. wrote:

 No. std.signals is old, old-fashioned but is still there 
 because there's no proposals to replace it and the standards 
 for std are high.


 Great. So there's a module in phobos that's not up to phobos' 
 standards and it doesn't get improved, because the standards 
 are too high. That's depressing.


It is. std.xml, std.json, std.stream...

The bar was raised in an effort to improve quality but it was 
done so at the expense of incremental improvements. I.e. it had 
to be near perfect or nothing. Given the size of the D community 
it is the latter and Phobos is effectively in maintenance mode.

If D had contributors lining up like say Python then it might be 
a different story but it doesn't.


 Btw. why is it old-fashioned?


I am only guessing but looking at the module I'd say the way it 
is structured doesn't fit in with "modern D", i.e. it isn't 
betterC friendly with  safe and  nogc, liberal use of  property 
etc.
Oct 18 2020
next sibling parent Andrei Alexandrescu <SeeWebsiteForEmail erdani.com> writes:
On 10/18/20 5:53 PM, norm wrote:

 On Sunday, 18 October 2020 at 16:27:43 UTC, Johann Lermer wrote:

 On Saturday, 17 October 2020 at 16:36:37 UTC, Basile B. wrote:

 No. std.signals is old, old-fashioned but is still there because 
 there's no proposals to replace it and the standards for std are high.


 Great. So there's a module in phobos that's not up to phobos' 
 standards and it doesn't get improved, because the standards are too 
 high. That's depressing.


 
 It is. std.xml, std.json, std.stream...
 
 The bar was raised in an effort to improve quality but it was done so at 
 the expense of incremental improvements. I.e. it had to be near perfect 
 or nothing. Given the size of the D community it is the latter and 
 Phobos is effectively in maintenance mode.
 
 If D had contributors lining up like say Python then it might be a 
 different story but it doesn't.


Well put.
Oct 19 2020
prev sibling parent reply bachmeier <no spam.net> writes:
On Sunday, 18 October 2020 at 21:53:06 UTC, norm wrote:


 It is. std.xml, std.json, std.stream...

 The bar was raised in an effort to improve quality but it was 
 done so at the expense of incremental improvements. I.e. it had 
 to be near perfect or nothing. Given the size of the D 
 community it is the latter and Phobos is effectively in 
 maintenance mode.


This might all be true, but does it matter? It's open source, so 
all you have to do is fork Phobos, make the changes you want, and 
then dump the final result into a package others can use. This 
can typically be done by editing a single file of source code. 
I've done it.

Incremental change is not held back by the high standards of 
Phobos. I don't think it started as a fork of std.xml, but there 
is https://code.dlang.org/packages/dxml Adding a Dub dependency 
is a low bar. (And for that matter, you wouldn't even have to use 
Dub for this purpose, you could just download a file or two and 
drop them into your project the same as any other D source files.)
Oct 19 2020
parent reply Johann Lermer <johann.lermer elvin.eu> writes:
On Monday, 19 October 2020 at 14:52:45 UTC, bachmeier wrote:


 This might all be true, but does it matter?


I firmly believe yes, it does matter. A buggy standard library 
certainly does not help in raising D's attractivness for 
programmers coming from other languages.
Oct 20 2020
parent bachmeier <no spam.net> writes:
On Tuesday, 20 October 2020 at 07:47:15 UTC, Johann Lermer wrote:

 On Monday, 19 October 2020 at 14:52:45 UTC, bachmeier wrote:


 This might all be true, but does it matter?


 I firmly believe yes, it does matter. A buggy standard library 
 certainly does not help in raising D's attractivness for 
 programmers coming from other languages.


I was referring to the part about how development stopped because 
it has to be perfect to get in. That's not the reason development 
stops. It stops because nobody wants to write the code. Mark the 
Phobos library as "do not use" (as has been the case for years 
with std.xml) and link to Dub projects that provide the 
functionality. There's no reason anyone needs to rely on Phobos. 
The programming world isn't perfect.
Oct 20 2020