Re: About String

[Georg Bauhaus <rm.dash-bauhaus@futureapps.de>]

Dmitry A. Kazakov schrieb:
> On Sun, 08 Jun 2008 17:19:11 -0400, Robert A Duff wrote:
> 
>> Maciej Sobczak <see.my.homepage@gmail.com> writes:
>>
>>> After all, with the possibility to initialize the new variable with
>>> arbitrarily complex expression (including function call), this is
>>> already the case and the whole declare-begin-end block is just
>>> reflecting some artificial separation.
>> I agree.  I suppose it comes from Pascal, where declarations and
>> executable code are completely separated.  It makes no sense in
>> Ada, where declarations are just as executable as statements.
> 
> I disagree. I think it does make sense because it clearly defines the scope
> of the declared variable.

Still, a somewhat *new* kind kind of handling exceptions in single
declarations looks interesting?

Given linear order of elaboration in declarative parts,
and thus the possibility of sequencing initialization
of local variables:

   procedure P is
      declare
         X1: constant T;  -- like Java final
      begin
         X1 := New_T(...);  -- may raise CE
      exception
         when Constraint_Error =>
             X1 := Fallback_T;  -- better than Java final
      end;
      X2: D := New_D(X1, ...);  -- safely refer to X1
   begin
      ...
   end P;