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From: "Alejandro R. Mosteo" <alejandro@mosteo.com>
Newsgroups: comp.lang.ada
Subject: Re: Mixing operators and dot notation
Date: Mon, 6 Jun 2016 15:58:12 +0200
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Xref: news.eternal-september.org comp.lang.ada:30635
Date: 2016-06-06T15:58:12+02:00
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On 06/06/16 10:10, briot.emmanuel@gmail.com wrote:
>> To give you the essence. I'm back to trying to get a minimal ReactiveX
>> (http://reactivex.io)-like thing working. The gist is that you can chain
>> many transformation operations:
>>
>> SourceType.Generate_Data
>>      .Op1 (...)
>>      ...
>>      .OpN (...)
>>      .Endpoint (Operate_With_Resulting_Transformed_Data);
>
>
> Funny, I have been playing with exactly the same purpose recently
> although I only started from the promises pattern, which I am now
> extending.
>
> https://github.com/briot/Ada-promises

Noted.

>
> I had exactly the same problems you had, and copy with using operators,
> so my current syntax is:
>
>        Get_Promise
>             and new Op1
>             and (new Op2 & new Op3)
>             and new Endpoint;
>
> (using tagged types for the operations). That's because things need to be
> type safe as well, so the operations are declared in generic packages,
> and therefore we can't use the dot notation here. I believe there could be
> some extension to the language here.

Talk about serendipity. Just last night I arrived at a solution I find 
satisfactory, and I see it's basically the same as yours (using "&" 
instead). From a cursory glance at your Ada-promises site I see that we 
had the same thinking about lambda functions too.

My RxAda outline is here:

https://bitbucket.org/amosteo/rxada/

Álex.

>
> Emmanuel
>