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Date: Thu, 3 Jan 2019 14:39:10 -0800 (PST)
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Subject: Re: Ada grammar rules for names too permissive?
From: olivermkellogg@gmail.com
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Xref: reader01.eternal-september.org comp.lang.ada:55182
Date: 2019-01-03T14:39:10-08:00
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On Tuesday, January 1, 2019 at 9:44:17 AM UTC+1, Dmitry A. Kazakov wrote:
> [...]
>       Never push semantic rules into syntax.

I'm not so sure about that:
A nice feature of ANTLR is that is supports semantic predicates which can be embedded in the grammar.
For example, using sem preds on the basis of symbol tables would permit discerning among indexed_component, type_conversion, function_call.

> The grammar as written is never the one actually used for whatever 
> purpose other than explanation or, maybe, validation.

The interesting question IMO is:
What are the necessary transformations for going from Annex P BNF plus informal description of semantic rules to the actual implementation grammar.

- Oliver