Subject: Re: [Boost-users] [program_options] Obtaining parameter order
From: Vladimir Prus (vladimir_at_[hidden])
Date: 2009-04-13 12:19:20
Adam Nielsen wrote:
>>> For example, a program to work with .zip files might work like this:
>>>
>>> zip --rename=one.bin:alpha.bin --add=one.bin --rename=one.bin:beta.bin
>>
>> The parse_command_line function returns vector<options> which is accurate
>> representation of what was found on the command line -- in particular:
>>
>> - the order of options is the same as on command line
>> - if there are multiple occurrences of the same option, those are not
>> collapsed and stay separate.
>>
>> Does this help?
>
> Yes! This works exactly as I need. Thanks!
>
> One question - parse_command_line() returns (eventually) a vector of
> basic_option. This basic_option class contains the name of the option and a
> vector of values.
>
> What is this vector used for? If a command line option has no value (e.g.
> "--verbose") then the vector is of course empty, and if the command line
> option has a value (such as "--output file.bin") then the vector contains a
> single value, so I'm wondering whether there's some syntax that will cause
> multiple values to end up in this vector, or is it there for use later on
> (when options are combined)?
You can declare an option that takes multiple values, so
--such-an-option a b c --another-option
will result in a vector of values containing 'a', 'b', and 'c'.
- Volodya