Re: [Fwd: F22 completes 11% of its Flight tests]

[Richard D Riehle <laoXhai@ix.netcom.com>]

In article <Dt7f4.2222$iy5.92651@typ12.deja.bcandid.com>,
	"jtarver" <jtarver@tminet.com> wrote:

>
>Bill Greene <wrg@Ganymede.com> wrote in message
>news:387D011B.2DC@Ganymede.com...

>> Also, it's not entirely accurate to say that Ada was intended to be
>> platform transparent.
>
>That is exactly the original selling point for the funding of Ada.

Well, not exactly.  One of the selling points for a language such
as Ada was portability, not transparency.  There is a difference.
In practice, most of Ada software has been portable.  The exceptions
have been low-level routines that incorporate platform-specific
information in their implementation.  For example, the interrupt
scheme for a VAX will be quite different from that on an PowerPC.

I think the extensions you cite are packages provided by the compiler
publisher that enable the programmer to take advantage of capabilities
of the targeted platform.  Such packages are quite common.  They do
not extend the language.  Rather, they use the abstraction model of
Ada exactly as originally intended.  

When measured against other languages for portability, Ada turns out
to be one of the most portable languages available -- especially the
current Ada 95 standard.  It is even more portable than Java since it
can be used in place of Java to create applets that run on the JVM. 

As to "selling points," one needs to look at the many other selling
points of Ada, as well.  These include one very big point:  the ability
of the compiler to catch the maximum number of errors as early as possible
in the development process.  From the perspective of software economics,
this turns out to be one of the most significant of Ada's "selling points."

Richard Riehle