Re: [Boost-users] [program_options] Named values

From: Vladimir Prus (ghost_at_[hidden])
Date: 2008-02-20 01:22:54

Igor Mikushkin wrote:

> 2008/2/19, Vladimir Prus <ghost_at_[hidden]>:
>> Igor Mikushkin wrote:
>>
>> > Hi!
>> >
>> > I have already asked this question about a month ago.
>> > But it wasn't answered and I suppose to repeat.
>> >
>> > I cannot find in docs how to create named vales
>> > for producing output like shown in this example from docs:
>> >
>> >    $bin/gcc/debug/multiple_sources --help
>> >    Allows options:
>> >
>> >    Generic options:
>> >      -v [ --version ]       : print version string
>> >      --help                 : produce help message
>> >
>> >    Configuration:
>> >      --optimization n       : optimization level
>> >      -I [ --include-path ] path : include path
>> >
>> > The "--include-path" option shown above has "path" parameter,
>> > what I have is "arg".
>>
>> The docs example appears to be stale -- the code always
>> produces 'args'. I think it's OK, because it relieves you
>> from the need to think out witty names for parameters. Above,
>> the word 'path' occurs three times on a line, and probably
>> does not add much value.
> 
> OK. Although I think that the ability to override this standard manner
> can't be redundant.
> 
>> > Also I don't understand how to restrict hidden values.
>> >
>> > For example I want command "myutil --help restrict this" to throw
>> > an exception because of "restrict" and "this" but it doesn't do it.
>>
>> Why? 'restrict' appears to the value of the option --help, and this
>> is an argument. What's wrong?
>>
> 
>  "--help" option doesn't has any arguments in my tool.
> Of course program_options processes all the arguments right
> and my tool works fine. But it just ignores separate words in the command line
> that does not started with "-" or "--". My tool does not have any commands or
> parameters like input files, etc. I ask if I can restrict commands like
> "myutil 1 2 3 4 5 the rabbit went out"

No. Anything that is not an option is assumed to be a parameter.

-  Volodya