Re: Ada and robots

[Huy Vo <vo@CTRON.COM>]

>Stephen Leake <Stephen.Leake@gsfc.nasa.gov>
>wrote
>Samuel Mize wrote:
>>
>> Note that I make some comments about the person Mr. Whiting quoted,
>> but none about Mr. Whiting.  Some quotations reformatted for length.
>>
>> Stephen Leake wrote:
>> >
>> > Matthew S. Whiting wrote:
>> >  ( second hand list of supposed Ada deficiencies )
>> ...
>> > > >*      Ada does not support discriminant unions (which are
>> ...
>> > This is precisely the Ada discriminant record:
>>
>> Ah, but you can't hand-code the discriminant values.  This makes it
>> harder to interface to existing C code, which of course makes C
>> fundamentally better.
>>
>Um, yes you can; that's what an enumeration representation clause is
>for; see RM13.4
>
>> Besides, you can't load the variable with one type and then read it
>> as another type.  In C it's simple and safe, while in Ada it requires
>> Unchecked_Conversion, which everyone knows is dangerous.
>
>Um, this just means Ada _labels_ unchecked conversion as dangerous. In C
>it may be "simple", but it is NOT "safe". (Maybe you forgot a smiley?)
>
Safe or not safe, it looks like Ada programs can crash on the field like
a previous poster admitted. The worse thing is that it leaves no trace
as to what leads to the crash.  And other posters have to come up with
ugly 'C hacks'  to provide traceback of Ada programs. There goes the myth
that Ada programs need no debugging.