Re: I am not understanding user defined exceptions

["Randy Brukardt" <randy@rrsoftware.com>]

"Robert A Duff" <bobduff@TheWorld.com> wrote in message 
news:wccfujnf042.fsf@TheWorld.com...
> "Randy Brukardt" <randy@rrsoftware.com> writes:
>
>> Most likely:
>>
>>      X : Integer := ...; -- Static constant
>>      X : constant Integer := ...; -- Non-static constant
>>      X : variable Integer := ...; -- Variable.
>>
>> Since the default should be the safest thing.
>
> Well, at least we agree on one thing.  It's odd that Ada got it right
> for parameters ('in' is the default), but got it wrong for object
> declarations (variable is the default).
>
> I'd be happy with:
>
>     X : Integer := ...; -- constant
>     X : var Integer := ...; -- variable

(1) Ada doesn't generally use abbreviations, thus "var" isn't a likely 
keyword.

(2) It's important that all properties that clients can depend upon are 
declarable, so clients aren't depending on accidental properties. (That's 
the whole principle behind private types.) Static is such a property, so it 
should be declarable (not necessarily have to be declared in all cases). 
[Indeed, it should be possible to declare static private types - a whole 
different kettle of fish.] Similarly, it would be nice if there was a way to 
prevent people from depending upon the subtype profile of a subprogram (so 
that it can later be changed if necessary). There's probably other such 
properties (one would like to include formal parameter names in this sort of 
restriction, but that would prevent named calls which would be evil.)

                                  Randy.