(In reply to comment #0)
> Created attachment 1574 [details]
> Patch
> 
> The attached patch extends CommandLine interface and allows requesting output
> of command line arguments help message using a couple of alternative methods.

ok, +1 for merging.

I didn't understand the changes to be honest. I mean, I'm ok with it but I couldn't find the "couple of alternative methods"

Created attachment 1648 [details]
Patch

Updated patch against the most recent changes in command-line.h|cc

The basic desire originally was (and still is) to be able to print out help message, in case scenario detects incompatible command-line arguments (rather than just exiting with just error message).  There are two basic changes:

1. Moving PrintHelp to public section of the class
2. Changing prototype of all Print* functions to accept output stream as a first argument and then implementing an overloaded operator>>.

By "a couple methods" I meant just "cmd.PrintHelper (std::cout)" and "std::cout << cmd", but I agree this was a little bit confusing :)

(In reply to comment #3)
> Created attachment 1648 [details]
> Patch
> 
> Updated patch against the most recent changes in command-line.h|cc
> 
> The basic desire originally was (and still is) to be able to print out help
> message, in case scenario detects incompatible command-line arguments (rather
> than just exiting with just error message).  There are two basic changes:
> 
> 1. Moving PrintHelp to public section of the class
> 2. Changing prototype of all Print* functions to accept output stream as a
> first argument and then implementing an overloaded operator>>.
> 
> By "a couple methods" I meant just "cmd.PrintHelper (std::cout)" and "std::cout
> << cmd", but I agree this was a little bit confusing :)


Does your documentation of PrintHelp() need updating, to match the commit message?

Also, is it operator >> or insertion operator<< ?

+   * Alternatively, an overloaded operator >> can be used:
+   * @code
+   *       CommandLine cmd;
+   *       cmd.Parse (argc, argv);
+   *     ...
+   *     
+   *       std::cerr << cmd;
+   * @endcode   
+   */

Is this something that should be patched into the tutorial and one or more examples?

Created attachment 1649 [details]
Fixup of previous patch

Oops. My mistake.  Uploaded the corrected commit with corrected documentation of PrintHelp and similar documentation for operator<<.

Are you suggesting to make a new example or modify some existing example to show potential usage?

(In reply to comment #5)
> Created attachment 1649 [details]
> Fixup of previous patch
> 
> Oops. My mistake.  Uploaded the corrected commit with corrected documentation
> of PrintHelp and similar documentation for operator<<.
> 
> Are you suggesting to make a new example or modify some existing example to
> show potential usage?

Yes, I was just suggesting to feel free to extend the tutorial or example in an appropriate place; many people only learn about features they see in the tutorials or examples.

I'll plan to push this later this week if there are no other comments.

changeset 48f66512ec9b

I noticed that one of the commits (http://code.nsnam.org/ns-3-dev/rev/5f6bab1bf0f4) undoes some of the previously added functions. In particular, it removes overloaded operator<< for CommandLine.

Is there a particular reason for this removal or is just an accident?

operator << (std::ostream, CommandLine0 restored in patch r10621 
http://code.nsnam.org/ns-3-dev/rev/c23778df1349