Re: [Boost-bugs] [Boost C++ Libraries] #2982: Required Arguments

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #2982: Required Arguments
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2009-11-04 10:10:57

#2982: Required Arguments
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 Reporter:  David Doria <daviddoria@…>          |       Owner:  vladimir_prus  
     Type:  Feature Requests                    |      Status:  new            
Milestone:  Boost 1.39.0                        |   Component:  program_options
  Version:  Boost Development Trunk             |    Severity:  Not Applicable 
 Keywords:  Required Arguments                  |  
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Comment(by s.ochsenknecht@…):

 I just checked if it is possible to place the check in notify(), but there
 is one problem. The  notify function just gets the variables_map parameter
 and not the options_description's which have the information about
 required options.

 I have following solutions in mind:

 1) in store() we store any required options with an empty value (if not
 occur) in the variables_map. In notify we then check for empty() and throw
 exception if empty() and required(). Any side effects? My preferred
 solution.

 2) we pass options_description's to notify() to be able to perform the
 cross check, but this breaks the interface (or we overload notify, but
 then its up to the user to choose the correct notify() ... :-(

 3) we store a reference/pointer to options_description's in variables_map.
 :-(

 ...

 Please comment. Thanks

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/2982#comment:5>
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