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Subject: Re: [boost] program_options negative numbers
From: Mateusz Loskot (mateusz_at_[hidden])
Date: 2011-02-18 16:43:22


On 04/02/11 09:39, Mateusz Loskot wrote:
> On 03/02/11 13:31, Andrzej Zielinski wrote:
>> I am using boost::program_options and found a problem with passing a
>> series
>> of positive/negative numbers.
>> i.e
>> myProgram.out --system 0 -2 2 -3
>>
>> Similar problem like in:
>> http://stackoverflow.com/questions/4107087/accepting-negative-doubles-with-boostprogram-options
>>
>> I do not want to disable short options. I want to make quotes working.
>>
>> So when I call
>>
>> myProgram.out --system '0 -2'
>> error: in option 'system': invalid option value
>
> A couple of months ago, I discussed it quickly with Volodya on the
> #boost IRC channel and here is a short recipe of how it could be solved:
>
> ####################################################################
> Nov 10 17:04:17 <mloskot> volodya: I think it's feasible to refactor
> the loops in the cmdline parser to handle multitoken options with
> negative numbers as values. I have an idea to add ::multitoken(int
> exact_tokens_num) and make parser consuming as much values as the exact
> number of tokens specified, regardless how the options look like
>
> Nov 10 17:04:26 <mloskot> volodya: what you think about this idea?
>
> Nov 10 17:05:30 <volodya> mloskot: well, I think that if that
> translates into min and max number of tokesn of the option being equal
> to that value, it seems sane
>
> Nov 10 17:05:53 <mloskot> volodya: yes, basically that would be the
> thing
>
> Nov 10 17:05:55 <volodya> and of course, when min=max, there's no
> need to guessing.
>
> Nov 10 17:05:59 <volodya> ok, sounds good.
> ####################################################################
>
> It's not a big problem, just lack of man power to solve.
> I suppose program_options would welcome relevant patches.

FYI, I have reported it as ticket so it wont be forgotten:

https://svn.boost.org/trac/boost/ticket/5201

Best regards,

-- 
Mateusz Loskot, http://mateusz.loskot.net
Charter Member of OSGeo, http://osgeo.org
Member of ACCU, http://accu.org

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