Re: Anonymous array clarification.(Better idea, I think.)

Re: Anonymous array clarification.(Better idea, I think.)

[McDoobie]

Okay, from the above posts in this thread, I think I might be getting
somewhere.

I'm thinking my problem stems from understanding the difference between an
"Object" and a type. As I'm coming from a C background, Objects and
Classes are real fuzzy for me.

So if I say...

	type foo_array is array(1..N) of character;  

this would be an Object declaration.  Then I would instantiate it
thusly....

	bar_array :  foo_array;

correct?

However if I say...

	some_chars : array(1..N) of character;

this would be just a simple array declaration, with none of the Object
Oriented properties  carried along with it.

And with the Object "foo_array" declared above, I could say ...

	type Upper_Case is subtype foo_array;

and it should work?

Am I beginning to get the picture?

McDoobie 
chris@dont.spam.me

Re: Anonymous array clarification.(Better idea, I think.)

[David C. Hoos]

----- Original Message -----
From: "McDoobie" <chris@dont.spam.me>
Newsgroups: comp.lang.ada
To: <comp.lang.ada@ada.eu.org>
Sent: Monday, August 20, 2001 4:40 PM
Subject: Re: Anonymous array clarification.(Better idea, I think.)


> Okay, from the above posts in this thread, I think I might be getting
> somewhere.
>
> I'm thinking my problem stems from understanding the difference between an
> "Object" and a type. As I'm coming from a C background, Objects and
> Classes are real fuzzy for me.
>
> So if I say...
>
> type foo_array is array(1..N) of character;
>
> this would be an Object declaration.  Then I would instantiate it
> thusly....
>
> bar_array :  foo_array;
>
> correct?
>
No.  Bar_array is an object declaration.  foo_array is a type declaration.

> However if I say...
>
> some_chars : array(1..N) of character;
>
> this would be just a simple array declaration, with none of the Object
> Oriented properties  carried along with it.
>
some_chars is also an object declaration, but of an anonymous array type.

> And with the Object "foo_array" declared above, I could say ...
>
> type Upper_Case is subtype foo_array;
>
> and it should work?

There is nothing yet to"work," since there are no executable statements,
only declarations.  In fact, you have declared no object of type Upper_Case,
so it does noting for you but to declare a type of which you have declared
no object.

None of whjat you've done so far has anything to do with the object-oriented
features of Ada.

It seems like you really need to get hold of a good Ada book.

>
> Am I beginning to get the picture?
>
> McDoobie
> chris@dont.spam.me
> _______________________________________________
> comp.lang.ada mailing list
> comp.lang.ada@ada.eu.org
> http://ada.eu.org/mailman/listinfo/comp.lang.ada
>

Re: Anonymous array clarification.(Better idea, I think.)

[Jeffrey Carter]

McDoobie wrote:
> 
> So if I say...
> 
>         type foo_array is array(1..N) of character;
> 
> this would be an Object declaration.  Then I would instantiate it
> thusly....
> 
>         bar_array :  foo_array;
> 
> correct?
> 
> However if I say...
> 
>         some_chars : array(1..N) of character;
> 
> this would be just a simple array declaration, with none of the Object
> Oriented properties  carried along with it.

This has nothing to do with object orientedness. Bar_Array is a variable
of type Foo_Array, and Some_Chars is a variable of an unnamed
(anonymous) array type.

> 
> And with the Object "foo_array" declared above, I could say ...
> 
>         type Upper_Case is subtype foo_array;
> 
> and it should work?

This will not work. Perhaps you mean

subtype Upper_Case is Foo_Array;

or maybe

type Upper_Case is new Foo_Array;

I can't tell what you're trying to accomplish here.

> 
> Am I beginning to get the picture?

Unfortunately, it doesn't look that way.

-- 
Jeffrey Carter

Re: Anonymous array clarification.(Better idea, I think.)

[Darren New]

McDoobie wrote:
> Am I beginning to get the picture?

You should also be aware that Ada uses the terms "class" and "object"
differently from most OO languages. 

-- 
Darren New / Senior MTS & Free Radical / Invisible Worlds Inc.
San Diego, CA, USA (PST). Cryptokeys on demand. dnew@san.rr.com
           When was sliced bread invented?