Re: [boost] Re: another program option feature request

From: Pavol Droba (droba_at_[hidden])
Date: 2003-06-09 01:13:22

On Mon, Jun 09, 2003 at 09:08:37AM +0400, Vladimir Prus wrote:
> Hi Pavol,
> 
> > I have a request regarding config file support in the program option
> > library. Currently when the parser encounters an unknown option in the
> > config file, parsing is stopped with an exception.
> > Together with fixed option definition, this feature disables a possibility
> > to have an arbitrary options in the config file, whose exact format is
> > not know prior to parsing.
> > 
> > An example:
> > 
> > I'd like to have something like this in the config file
> > 
> > <conf-file>
> > 
> > [module]
> > 
> > file-count = 3
> > 
> > file-name1 = 001.aaa
> > file-name2 = 002.aaa
> > file-name3 = 003.aaa
> > 
> > </conf-file>
> > 
> > 
> > where the number of file-name* lines is not know before parsing, and it is
> > up to user to specify as many as she wants, or the format and number of
> > options is dependant on some other option ( i.e. file-count )
> > 
> > I think, that it would be nice to be able to force the parser to accept
> > also the options not described in the option_descriptions and have a way
> > to work with them.
> 
> In fact, there's a (undocumented) feature which applies to your case:
> 
>   desc.add_options()
>         ("file-name*", ....)
> 
> After this, every option starting with "file-name" will be accepted. Is this
> appropriate for your use case?
> 
> - Volodya

Well, it looks fine, but still, there can be other cases which could not be coverd by
a simple wildcard like this.

I think, it would still be benefitial if there would be possibility to parse options which have
not been described.

Pavol