Re: 11.6

["Matthew Heaney" <matthew_heaney@acm.org>]

In article <wcchfiexwj3.fsf@world.std.com> , Robert A Duff 
<bobduff@world.std.com>  wrote:

>>   procedure Push
>>     (Stack : in out Stack_Type;
>>      Item  : in     Item_Type) is
>>
>>      subtype Top_Range is Positive range 1 .. Stack.Size;
>>
>>      Top : Natural renames Stack.Top;
>>   begin
>>      Top := Top_Range'(Top + 1);    --???
>>      Stack.Items (Top) := Item;
>>   end Push;


Compare that Push with this one:

 procedure Push
   (Stack : in out Stack_Type;
    Item  : in     Item_Type) is

    Stack_Not_Full : constant Boolean range True .. True :=  --???
      Stack.Top < Stack.Size;

    Top : Natural renames Stack.Top;
 begin
    Top := Top + 1;
    Stack.Items (Top) := Item;
 end Push;


Can the marked line be optimized away per 11.6?


--
Why stop at evolution and cosmology, though? Let's make sure that the
schoolkids of Kansas get a really first-rate education by loosening up
the teaching standards for other so-called scientific ideas that are,
after all, just theories. The atomic theory, for example. The theory of
relativity. Heck, the Copernican theory--do we really know that the
universe doesn't revolve around the earth?

John Rennie, Scientific American, Oct 1999