Hi again,
Section "Tutorial" ------------------------
1. I don't like that the example hardcodes strings.
Could you explain? --------- writing const char* help = "help"; would enable the compiler to catch spell-errors in the constants.
2. each line should have a comment about what it does.
Actually, that would duplicate explanations that are already in the tutorial. Don't you think? ------------------ I'm in doubt :-) I do like comments because they can easily be compared to code; when you're reading block text, it can be harder to focus on where the comments apply.
9. Could this way of specifying composing()/default_value() be of any use
option += option<int>( "xx", "xx msg" ), option_with_default<int>( ""yy", var_name, 0, "yy msg" ), option_with_compose< vector<string> >( "zz", "zz msg" );
?.
I think that syntantically, it requires the same number (or even larger) number of characters. Besides, what if you want to specified both default value and 'composing' flags? options_with_default_and_compose looks too long. --------- yeah, then what about option += option<int>( ""xx"", var_name, compose_flag | other_flag ) ? That use of flags might be more idiomatic.
10. This
po::options_description cmdline_options; cmdline_options.add(generic).add(config).add(hidden);
might be
po::options_description cmdline_options; cmdline_options += generic, config, hidden;
?
Interesting! I just found some-years-old code of mine which provides support for such initialization. It worked for vectors, like: v << 1, 2, 3, 4, 5, 6; but can be easily used for +=, too. I'm just not sure this is justified here. -------------- Actually, one could choose to use my assign library if it gets accepted. You would probably only have to write one overload of operator+= so it can recognize your types. There is also another use. Let's say you make a function add(): program_options po; add( po )( "xx", df, "xx msg)(...)(...) that should work ou of the box with different tuplesizes. Making add() and operator+() is about the same amount of work, probably 3-4 four lines each. br Thorsten