Re: How can I avoid Using a Semaphore?

["DuckE" <nospam_steved94@home.com>]

"Robert Dewar" <robert_dewar@my-deja.com> wrote in message
news:94co6t$v27$1@nnrp1.deja.com...
> In article <0Cka6.290338$U46.9207275@news1.sttls1.wa.home.com>,
>   "DuckE" <nospam_steved94@home.com> wrote:
> > In my opinion this is one of the weak points of Ada 95.  It
> > would have been better to not have the 'input and 'output
> > pre-defined for built in types (as a part of the language)
> > but to include a package for defining these
> > attributes.  That way an arbitrary representation of built in
> > types could be used with streams when desired.
>
>
> I don't see your point here. Surely you are not arguing in
> favor of REQUIRING people to define their own stream attributes
> for types, that would be a huge pain for the most common use
> of stream attributes.

No I'm not in favor of requiring people to define their own stream
attributes.

>
> There are two possibilities
>
> 1. You want to control stream behavior on a type by type basis.
> This you can do perfectly fine, by just avoiding built in types
> like Integer, which is good practice anyway, and then define
> the stream attributes to work however you want.
>
> 2. You want to control stream attributes globally (as is
> permitted in GNAT by replacing the System.Stream_Attributes
> unit), but you seem to say in the same message that you do NOT
> like the fact that in GNAT this approach results in the default
> routines applying to everything.
>

I believe there's a third:

3. You want to control stream behavior on a type by type basis for all types
including built in types.  You also include a package containing streaming
definitions for built in types that may be included using a WITH statement.

This behavior would be more consistent with operation of functions like
"sin" and "cos" that are not pre-defined, but included in a standard
package.

> It really seems like Ada 95 does EXACTLY the right think in the
> terms you have layed out here, you will have to be a lot
> clearer in making your acase that something is missing. Perhaps
> you can give at least a sketch of what you would like to see.
>

Perhaps I would like to see something like:

package Ada.Streams.Built_In_Types is
  --
  --  Define 'Input, 'Output for built in types
  --
end Ada.Streams.Built_In_Types;

And then in my code I have the control to create:

package Steves_Streaming_For_Built_In_Types is
  --
  --  Define 'Input, 'Output for built in types
  --
end Steves_Streaming_For_Built_In_Types;

> From where I sit, it seems like your problem is reasonable,
> and easily addressed with the current language features, and
> i can't see any addition to these features which would be
> helpful in this particular case.
>

For me it's easier to just stay away from streaming.  For one thing, the
behavior is implementation dependent.  For another, I have been quite
effective at getting things done without it.

>
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