Re: Interesting article on ARG work

["Dan'l Miller" <optikos@verizon.net>]

On Sunday, April 8, 2018 at 2:46:15 AM UTC-5, Dmitry A. Kazakov wrote:
>     if Foo then
> @     Bar;
> @  end if;
> @  if Boo then
>        Baz;
>     end if;
> 
> would not be legal either.

Where ␠ is the ASCII/ISO646 space character (presented as a graphical character for visualization herein),

    if Foo then
␠     Bar;
␠  end if;
␠  if Boo then
       Baz;
    end if;

and

    if Foo then
--     Bar;
--  end if;
--  if Boo then
       Baz;
    end if;

both are legal Ada statements, spurious and non sequitur evocations of the ARM notwithstanding.

In general, Dmitry, you seem to not understand that a generalized left-right (GLR) parser would parse both sides of the @ concurrently.  Your entire premise is that it is impossible to parse both presence and absence of @ at the same time.  In GLR, you are incorrect.