Re: Environment variables

[stt@houdini.camb.inmet.com (Tucker Taft)]

Robert A Duff (bobduff@world.std.com) wrote:

: In article <dewar.846951642@merv>, Robert Dewar <dewar@merv.cs.nyu.edu> wrote:
: >This is not an extension to the language. Any Ada compiler can provide
: >additional useful packages

: Robert, you have a strange definition of "extension".  I would say: This
: *is* an extension to the language.  Any Ada compiler can provide
: extensions of this nature (additional useful packages).  Other
: extensions that are explicitly allowed by the RM are additional pragmas
: and attributes.  Most extensions are of course DISallowed by the RM.

: To the Ada programmer, this thing is an extension, in the sense that it
: provides functionality available on GNAT, which may or may not be
: available on some other compiler.  In practical terms, if you use a
: different compiler, your program will stop working.

I think the big difference with this kind of extension is that
you can write such packages yourself, without having to talk to the
compiler vendor.  On the other hand, other permissible "extensions"
like additional pragmas and attributes are almost always restricted
to the compiler implementor.

: - Bob

-Tucker Taft   stt@inmet.com   http://www.inmet.com/~stt/
Intermetrics, Inc.  Cambridge, MA  USA