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Subject: Re: [proto] Visitor Design Pattern
From: Joel de Guzman (joel_at_[hidden])
Date: 2010-10-23 20:10:25

On 10/24/2010 2:18 AM, Thomas Heller wrote:
> On Saturday 23 October 2010 19:47:59 Eric Niebler wrote:
>> On 10/23/2010 10:45 AM, Thomas Heller wrote:
>>> On Saturday 23 October 2010 19:30:18 Eric Niebler wrote:
>>>> On 10/23/2010 10:12 AM, Eric Niebler wrote:
>>>>> I've tweaked both the traversal example you sent around as well as my
>>>>> over toy Phoenix. Tell me what you guys think.
>>>> Actually, I think it's better to leave the definition of "some_rule"
>>>> alone and wrap it in "named_rule" at the point of use. A bit cleaner.
>>>> See attached.
>>> I like that.
>>> With that named_rule approach, we have some kind of in code
>>> documentation: Look, here that rule is a customization point.
>> Exactly.
>>> Why not just rule? Less characters to type.
>> I almost called it "rule", but *everything* in Proto is a rule including
>> proto::or_ and proto::switch_. What makes these rules special is that
>> they have a name.
> True. But you could look at proto::or_ and proto::switch_ or any other
> already exisiting rules as anonymous rules. While rule or named_rule
> explicitly name them.

Well, in parsing land, rules are always named. There's no such thing
as anonymous rules, AFAIK. What's the counterpart of "parser" in the
proto world?


Joel de Guzman

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