Re: Would an *AdaScript* language be a good / bad idea?

[dewar@gnat.com (Robert Dewar)]

"Steve Doiel" <nospam_steved94@attbi.com> wrote in message news:<bWsE8.34889$UV4.7322@rwcrnsc54>...
> "Robert Dewar" <dewar@gnat.com> wrote in message
> news:5ee5b646.0205140618.2d789fc9@posting.google.com...

> Your definition of "scripting language" is certainly different from mine.  I
> did a google search to find a definition and found:
> http://hotwired.lycos.com/webmonkey/glossary/scripting.html
>  which is consistant with how I would describe a scripting language.

Here is the quote in question:

 A scripting language is a simple programming language used to write
an
 executable list of commands, called a script. A scripting language is
a high-
 level command language that is interpreted rather than compiled, and
is
 translated on the fly rather than first translated entirely.
JavaScript,
 Perl, VBscript, and AppleScript are scripting languages rather than
general-
 purpose programming languages. 

I find this definition silly. All these languages can perfectly well
be compiled, and any general purpose programming language can be
interpreted.
The difference between interpretetation and compilation is an
implementation
detail that has nothing whatever to do with the language.

For the most part, the distinction between scripting languages and
general
purpose programming languages is bogus (and ends up being an excuse
for some
extraordinarily poor language design flying under the "scripting
language"
banner).

When I say that we use Ada "as a" scripting language, what I mean is
that we
use Ada as a (perfectly satisfactory) language for achieving the kind
of thing
that is often done in a scripting language (by the way such languages
often
come along not only with bad designs, but bad software practices,
including
sloppy design and lack of proper documentation). 

To the extent that scripting language means very-high-level-language
in the
sense of SETL or SNOBOL4 or other garbage collected dynamic languages
with
complex data structures, then that's interesting, but such features
are by
no means essential for writing an "executable series of commands".

P.S. If you disagree with the claim that these languages can be
compiled, please first read my article in SP&E 1977 on SNOBOL-4
implementation.

> While I agree that anything that may be done with a scripting language may
> also be done with a general purpose compiled language, IMHO they are not the
> same thing.

If you want to adopt the above definition, then the main thing that
makes an
important difference to you is that the language must be interpreted.
But how
can this possibly per se be an advantage. You might want fast
compilation,
but that's certainly possible (SPTIBOL/370 compiles at tens of
millions of
lines a minute, essentially instantaneous, even for quite complex
operations).
You might want high level language features (but that's achievable in
compiled
implementations. Perhaps you want very slow execution -- true, that is
harder
to achieve without inefficient interpretation :-) :-)