Re: Ada 2012: In-out parameters for functions

[Adam Beneschan <adam@irvine.com>]

On Sunday, May 5, 2013 3:24:50 AM UTC-7, Niklas Holsti wrote:
> On 13-05-04 02:29 , Randy Brukardt wrote:
> 

> How about reusing the mode keywords:
> 
>    Proc (
>       In_Param  => in A,
>       Out_Param => out B,
>       In_Out_Param => in out C);
> 
> The mode keywords would be optional, of course, thus this extension
> would be upwards compatible with current Ada. Note that this syntax can
> be used with positional association calls, too:
> 
>    Proc (in A, out B, in out C);
> 
> An alternative, perhaps more English-like, would be to put the mode
> keywords in front of the formal parameter:
> 
>    Proc (
>       in In_Param  => A,
>       out Out_Param => B,
>       in out In_Out_Param => C);
> 
> but I like the first form better, because its form and format are more
> familiar, especially when the "=>" are vertically aligned.

I checked my archive of Ada-Comment mail, and it seems we had this exact discussion around March 2009.  It looks like I suggested one of the syntaxes you mentioned, and the people who commented afterward seemed to be split about evenly between those who like the idea and those who hated it.  (You contributed a comment too, on the "like" side.)  It doesn't look like this was ever turned into an AI or an AC, though; at least, I can't find it.  Bob Duff was the one who pointed out how Ada 79 handled it.

                          -- Adam