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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: Interesting article on ARG work
Date: Mon, 9 Apr 2018 18:30:36 +0200
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Xref: reader02.eternal-september.org comp.lang.ada:51417
Date: 2018-04-09T18:30:36+02:00
List-Id: <comp.lang.ada>

On 2018-04-09 18:12, Niklas Holsti wrote:

> For example, the text
> 
>      if Foo then
>         Bar;
> @   else
> @      Baz;
>      end if;
> 
> would be parsed in four ways, according to the four combinations of 
> choices (enabled/disabled) for the two @ signs:

[...]

It is a trivial recursive-descent parser. "else" cannot follow "@", 
because there is no statement starting with "else". Full stop.

You compile all code, always, taking choices at the stage of code 
generation. Simple as tooth powder.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de