Re: newbie inquiry

[Stephen Leake <stephen.a.leake.1@gsfc.nasa.gov>]

"Steven Shaw" <steve.shaw@uq.net.au> writes:

> Features I kinda know Ada has (but might be wrong)
>     * modules

Called 'packages'

>     * fixed string and dynamically growing strings (excellent) 

yes

>     * generics

yes

> Features I'm hoping Ada has:
>     * gc

I assume you mean "Garbage Collection" here. The Ada standard allows
garbage collection. Most implementations don't provide it. Those
targeted at the Java virtual machine do provide it.

>     * multiple interface inheritence (like Java, m3 doesn't have it)

The Ada standard does not provide this. The Ada compilers targeted at
the Java virtual machine have extensions that do provide it.

>     * fast language interoperability with C (ffi and data sharing)

I'm not clear what you mean. If you mean Ada functions can efficiently
call C functions, and vice versa, then yes, Ada has this.

>     * ability to put data/objects into shared-memory for sharing between
> processes

This is not in the Ada standard, nor in any other language standard,
that I know of. I don't know of any language that has the notion of
"process"; many have "task" or "thread", but they share an single
address space. 

This is typically done by importing an operating system function,
which can easily done by Ada code.

>     * speed of C?

Yes, some Ada compilers produce machine code that is as fast as that
produced by some C compilers, for equivalent input source code. The
converse is also true :).

>     * libraries for database access, sockets/protocols, xml

Yes, although probably not as much as C or C++ or Java or Cobol.

> The Ada spec is very big. 

In page count, it's smaller than the C++ spec.

> Is it all implemented in gnats? 

In GNAT, yes. Other compilers implement most of Ada; they leave out
some of the optional annexes.

> Are there features in the spec that could/should be avoided?

No. Unless you are doing hard real-time, but that's not a language
implementation issue.

-- 
-- Stephe