Re: A minimal LL(1) parser generator ?

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/

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