Re: Ada 2012: In-out parameters for functions

["Randy Brukardt" <randy@rrsoftware.com>]

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"Yannick Duchêne (Hibou57)" <yannick_duchene@yahoo.fr> wrote in message 
news:op.wwlyp5ymule2fv@cardamome...
>Le Sun, 05 May 2013 12:24:50 +0200, Niklas Holsti 
><niklas.holsti@tidorum.invalid> a écrit:
>
>> How about reusing the mode keywords:
>>
>>    Proc (
>>       In_Param  => in A,
>>       Out_Param => out B,
>>       In_Out_Param => in out C);
>>
>>
>> An alternative, perhaps more English-like, [.]
>>
>>    Proc (
>>       in In_Param  => A,
>>       out Out_Param => B,
>>       in out In_Out_Param => C);
>>
>
>But may be the first is more Chinese-like :P (I don't know, I don't know 
>Chinese)
>
>Not joking, the first looks better to me, it better express what it means 
>as the mode is closer to the actual parameter which is the subject of the 
>mode (the same way at the declaration, it is closer to the type, which is 
>the best to me for a similar reason).
>
>Seems this topic was not discussed at all for Ada 2012.

Not at all true. It was considered as part of AI05-0144-1, the AI that added 
the order-of-evaluation legality checks to the language. We decided to do 
nothing because there was no agreement on what syntax to use (as noted in 
this thread) and there also was a minority of people who thought it was a 
bad idea (also noted in this thread).

It's true that it didn't get a separate AI, but it was included in the AI 
dealing with the problem of function calls with side-effects -- which is the 
only important reason to consider it. We create AIs for *problems*, not for 
*solutions*.

                               Randy.