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From: anton@mips.complang.tuwien.ac.at (Anton Ertl)
Newsgroups: comp.compilers
Subject: Re: A minimal LL(1) parser generator ?
Date: Thu, 02 Jan 2020 17:25:14 GMT
Organization: Institut fuer Computersprachen, Technische Universitaet Wien
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carlglassberg@gmail.com writes:
>On Tuesday, December 31, 2019 at 8:42:51 AM UTC-8, Anton Ertl wrote:
>> carlglassberg@gmail.com writes:
>> >Gray's meta notation uses a postix operator "&&" for "separator list".
>...
>> >If Gray: "a b &&" ---> EBNF: "a { b a }"
...
>> >"a b && c &&"
...
>Should that be ?
>a {b a} { c a {b a}}

Yes.

>Also, would
>  a b && c d &&

I assume you mean a concatenation of "a b &&" and "c d &&".  In Gray
syntax that would be

(( a b && c d && ))

>parse as:
>  a { b a } c { d c }

Yes.

>or as:
>  a { b a } c { d a { b a } c }

If you want that, you would write it as

(( a b && c )) d &&

&& is just a binary postfix operator.

- anton
--
M. Anton Ertl
anton@mips.complang.tuwien.ac.at
http://www.complang.tuwien.ac.at/anton/