Re: [Boost-users] [program_options] Obtaining parameter order

Subject: Re: [Boost-users] [program_options] Obtaining parameter order
From: Vladimir Prus (vladimir_at_[hidden])
Date: 2009-04-06 05:24:30

Adam Nielsen wrote:

> Hi everyone,
> 
> I'm writing a program that needs to know the order that parameters are
> supplied in, but I can't find anything in the docs about this.
> 
> 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 initial --rename would need to be acted upon first, before --add
> (otherwise one.bin would get overwritten) and likewise the last --rename must
> be acted upon after --add, otherwise the wrong file (or no file) would be
> renamed.  If I use normal string vectors the order of the parameters will be
> lost so this won't work.
> 
> Is this sort of parsing possible with program_options, or will I need to
> resort to writing my own command-line parsing code?

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?

- Volodya