Re: RE: RE: Ada 0y wish list:

[Ted Dennison<dennison@telepath.com>]

In article <mailman.982270874.22619.comp.lang.ada@ada.eu.org>, Beard, Frank
says...
>
>What I had envisioned is that it would work very similar
>to an access type.  However stack space is controlled for
>an access type would be the same way to control the stack
>space for the deferred by reference type.
>
>As for the size, it would deviate slightly from access types,
>in that to get the size of an access type it is X.all'size.
>For the deferred type it would still be X'size, because the
>compiler would know that it's a deferred type and do the
>X.all'size equivalent, transparent to the user.

You seem to be operating on the old maxim that "any problem can be solved by
adding an additional level of indirection." However, I'm not sure this is one of
those cases. Whether its implemented as a stack object or a heap object does not
change the fact that the referencing code is going to have to be generated to go
out and get X bytes for the object from somewhere, and that code will have to be
recompiled whenver you change the source file that contains the calculation of
X.

Of course adherents to the indiection priciple I mentioned above would just
point out that X itself could be accessed as a variable instead of a constant,
even though it won't ever change within the type's scope. Yuk. 

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