title: Can one add boost program_options and parameters after CLI parsing is finished?
body: <p>The boost.program_options library stores and allows programmatic access to parameters provided on the command line when the program was run.</p>
  
  <p>Is it practical to call some library function (unknown to me, or easy to code) to instantiate options/parameters, also change value parameters on an option, once the program is running and has already parsed all CLI arguments? In other words, could one simply fire up (ie. add) existing options already configured in the source code, but not mentioned at the time of invocation?</p>
  
  <p>Why? Let's say the program has a GUI and the user wants to update some setting set at the command line.</p>