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From: Robert A Duff <bobduff@world.std.com>
Subject: Re: scripting/extension language for Ada (we have an opportunity
 here)
Date: 2000/02/16
Message-ID: <wccputwc1ft.fsf@world.std.com>#1/1
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Sender: bobduff@world.std.com (Robert A Duff)
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Organization: The World Public Access UNIX, Brookline, MA
Newsgroups: comp.lang.ada
Date: 2000-02-16T00:00:00+00:00
List-Id: <comp.lang.ada>

"Samuel T. Harris" <samuel_t_harris@Raytheon.com> writes:

>... So I don't need syntax non-terminals
> such as function_call_or_array_index_or_qualified_aggregate
> with all the complexity involved. The semantics
> still have to verify the appropriate nature of
> the element.
> 
> Given this, I believe you would agree that the substitution
> of () for [] and {} would now be trivial. 

Yes.

But the simplification of the grammar is fairly minor, when compared
with the complexity of overload resolution.

There may be good and bad things about "[", but I wouldn't say "["
greatly simplifies the compiler/interpreter, as you've defined it.

By the way, aggregates (qualified or not) can be syntactically
distinguished from function calls and whatnot.  The aggregate issue is
the potential confusion between a parenthesized expression and a
one-element positional aggregate.  (I consider it a design flaw in Ada
that there are no one-element and zero-element positional aggregates.
But with you're "trivial substitution" model, you can't solve that
problem.)

- Bob