Re: Ada2012 : Expression functions and extended return statements

["J-P. Rosen" <rosen@adalog.fr>]

Le 06/01/2012 10:45, stefan-lucks@see-the.signature a �crit :
> On Fri, 6 Jan 2012, Martin wrote:
> 
>> Also, on the topic of extended return statements...
>>
>> What's the rational for having to explicitly repeat the return type?
>> Seems rather redundant to my eyes. I wouldn't have minded:
> 
> I guess, this is because the object actually returned may not necessarily 
> be of exactly the same type of subtype as the declared return type -- like 
> the ordinary return statement. 
That's a good reason, but there is also a general principle that
whenever an object is declared, it's type appears in the same
declaration. This means that when you read the code, you know the type
of the object, without needing to look elsewhere - for example, renaming
could have used the type of the renamed object, but then the reader
could be forced to follow a chain of renaming declarations to discover
the type of the object.

In Ada, we favour the reader over the writer, don't we?

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