Proto for Boost mailing list page: Re: [proto] Visitor Design Pattern

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?

Regards,
-- 
Joel de Guzman
http://www.boostpro.com
http://spirit.sf.net