Re: [Boost-users] Spirit Newbie (balanced parentheses)

Subject: Re: [Boost-users] Spirit Newbie (balanced parentheses)
From: Joel de Guzman (joel_at_[hidden])
Date: 2010-04-20 20:25:55

On 4/20/2010 1:14 PM, OvermindDL1 wrote:
> On Mon, Apr 19, 2010 at 8:22 AM, Lars Rohwedder<L.Rohwedder_at_[hidden]>  wrote:
>> EricB schrieb:
>>> is there any way to manage this with 1.6.4
>>
>> If only need to checked whether the string contains the same number of
>> '(' and ')' what about
>>
>> int counter=0;
>>
>> rule<>  r = ch_p('(')[increment_a(counter)]>>  ~ch_p(')')>>
>> ch_p(')')[decrement_a(counter)]
>>
>> if(counter!=0)
>> {
>>         // unbalanced!
>> }
>
> Unnecessary, slower, and error-prone.  There is still a 'raw'
> equivalent in Spirit1 as I recall, but I do not know the syntax, you

Spirit1 is always "raw" in the sense that it is basically a
transduction parser and returns the iterators to the matching
range in the input.

Regards,
-- 
Joel de Guzman
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