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Re: Very minor grammar tweak

This page is part of the web mail archives of SRFI 110 from before July 7th, 2015. The new archives for SRFI 110 contain all messages, not just those from before July 7th, 2015.



Looks good to me.

foo
  \\
  \\

===>

(foo)

?

whereas:

foo

===>

foo

?

Sincerely,
AmkG

On 7/31/13, David A. Wheeler <dwheeler@xxxxxxxxxxxx> wrote:
> I intend to include a very minor grammar tweak.
>
> Previously "(GROUP_SPLIT | scomment) EOL DEDENT" was illegal because
> there was no way to return an "empty" value.
> Oh, wait, we can do that now!  So we may as well allow it.
> That would permit, for example:
> a b c
> !   d e
> !   #| this scomment is the last child line |#
> => (a b c (d e))
>
> This removes one token from the grammar, and a few lines
> from the implementation.  Here's the grammar change:
>
>  group_line returns [Object v]
>    : (GROUP_SPLIT | scomment) hs /* Initial; Interpet as group */
>        (group_i=it_expr {$group_i} /* Ignore initial GROUP/scomment */
>         | comment_eol
>           (INDENT g_body=body {$g_body} /* Normal GROUP use */
> -          | same {empty_tag} )) ;
> +          | {empty_tag} )) ;
>
>
> Comments?
>
>
> --- David A. Wheeler
>
>