Re: Ada-Oriented GUI

["Alejandro R. Mosteo" <alejandro@mosteo.com>]

On 21/03/18 14:58, Dan'l Miller wrote:
> On Wednesday, March 21, 2018 at 4:49:39 AM UTC-5, Alejandro R. Mosteo wrote:
>> On 19/03/18 15:10, Dan'l Miller wrote:
>>> I will need to take a portion of that back; there was some initial attempt at an RxAda that was reported last year:
>>>
>>> https://www.auto.tuwien.ac.at/~blieb/AE2017/presentations/RxAdaSlidesShort.pdf
>>>
>>> Perhaps this initial foray into an RxAda by Alejandro Mosteo is a starting point, or at least a prior reference to critique.
>>
>> RxAda is right now somewhat down in my stack of priorities, but actually
>> a demo over GtkAda/Gnoga is among the things I want to attempt sooner or
>> later.
>>
>> Álex.
> 
> I was hoping that you would reply to this thread.  Thank you, for the reply and for all your valuable & appreciated work on RxAda.  (Comp.lang.ada is more exciting when principle people contribute their expertise regarding fresh trends in Ada, rather than merely students seeking to cheat on their homework/test questions.) Is RxAda released publicly?  If not yet, might RxAda be released publicly as part of that GtkAda/Gnoga demonstration?

Thanks for these kind words. Sure, the repository is public: 
https://bitbucket.org/amosteo/rxada

> Also, (other than lack of free time) what has been the biggest obstacle to your development of RxAda?  Ada lacks lambdas/anonymous-subroutines but even the RxJava community sometimes prefers named methods over lambdas in app-domain code that utilizes RxJava, even in the latest versions of Java that have full-fledged lambdas in the language now.  What other language features or lack there of in Ada cause concern in your development of RxAda?  Have you envisioned language features unique to (current or future) Ada that would allow RxAda to go beyond the state of the art in the Rx libraries for all the other languages?

There are some thoughts about my experience writing RxAda in the website 
above. Besides that, I mostly concur with what Emmanuel Briot has said 
in another reply.

The need for so many generics is troublesome. I tried to make the 
library as easy to use as I could, but I couldn't go below one 
instantiation per user type and per type transformation. I haven't yet 
used RxAda in any real project, so I still lack the hands-on experience 
to see to what extent it is practical or not (hence my desire to test it 
with a real GUI).

I missed lambdas a bit, but not as much as I expected to. My recent 
experiences with expression functions make me think that those could be 
good candidates for "lambdification". As for your comments about the 
RxJava community, I'm afraid I don't know. I used for a while RxJava for 
some Android apps but then I had to move on. Though it was enough to get 
me sufficiently excited about it to write RxAda.

Java really has managed a hit with its implicit generics, though the 
editor I was using, the IntelliJ one, gets half of the merit with its 
on-the-fly suggestions for simplifications.

Also, the twisted use of generics + interfaces + "&" operator made me 
feel that I was using Ada in a way that was not the intended one. But it 
compiles and runs, so, who knows.