Re: [boost] Re: Formal Review: Command Line & Config library

From: Pavol Droba (droba_at_[hidden])
Date: 2003-05-23 01:29:05

Hi

On Fri, May 23, 2003 at 09:15:58AM +0400, Vladimir Prus wrote:

[snip]
 
> I'll keep this in mind. In fact, I plan to convert all the documentation
> into BoostBook is the library is accepted. The Doxygen is very nice --- in
> fact, it helps very much to keep everything documented. But I found it
> rather limiting for writing various "overview" pages. Hope new
> documentation will be better.

Great.

> > * Validation
> >    
> >    Library allows to supports validation and parsing of option parameters,
> >    but I thinks it is rather limited. It is possible to define
> >    user-specific behaviour, but it would be helpful, if some common
> >    formats would be suported.
> > 
> >    For instance:
> >       * Various integer types ( not just int ) with boundary checking.
> >         Something like
> >                paramter<int>( "count", 1, 4, &count ) // 1-Min and 4-Max
> >                value
> 
> It's funny that the very first prototype version had this facility. In
> surely can be added to the current version if there's such need.
> 
>

I like the idea proposed by Tanton. po::parameter should have a validation
predicate as an argument. 
A reasonable set of arguments can be provided by library, and the user can always
provide a specific ones.

 
> >       * Format specification and checking for string. Regex specification
> >       of something like scanf would be nice.
> >         This can be useful for example to check if the parameter is a
> >         filename.
> 
> Could you clarify a bit how scanf-like specification can work? You mean it
> can be used to specify syntax? 
> 

I mean something like "%02.4f" or something like that... it is just an idea. If there
would be a validation predicate as an argument, regex library can be used to define
regex predicate which would cover most of the cases.

> > * Environment & Others
> > 
> >    The library tries to unify the access to program options from command
> >    line and from ini files. This is very nice feature because it is
> >    removing the need for doing generaly the same thing twice. It would be
> >    nice if some other sources of paramers could be incorporated as well.
> >    Particulary the enviromnmet is often used to exchange arguments. Given
> >    the fact that it consist of a set of pairs "variable=value" it is very
> >    similar to the ini file and so it souldn't be hard to implement.
> 
> Thanks for the suggestion! It's quite right.
>  
> >    For windows platform the registry comes to play as another source of
> >    options.
> 
> Yep, that source was considered as alternative from the very start. I've
> seen some project start with a command line, then add config files and then
> need registry on Windows. Registry is not yet supported because I wanted to
> find out if there's support to the idea of uniform access to all
> configuration means.

I definitely like the idea of the uniform access. It would be only welcome if the library
can cover more sources of options.

Pavol