/optparse

C++ implementation of optparse (header-only fork of https://github.com/weisslj/cpp-optparse)

Primary LanguageC++

optparse

Build status

This is yet another option parser for C++. It is modelled after the excellent Python optparse API. Although incomplete, anyone familiar to optparse should feel at home: https://docs.python.org/library/optparse.html

Copyright (C) 2010 Johannes Weißl <jargon@molb.org>

License: your favourite BSD-style license

Design decisions

  • elegant and easy usage more important than speed / flexibility
  • shortness more important than feature completeness
    • no unicode
    • no checking for user programming errors

Why not use getopt/getopt_long?

  • not C++ / not completely POSIX
  • too cumbersome to use, would need lot of additional code

Why not use Boost.Program_options?

  • boost not installed on all target platforms (esp. cluster, HPC, ...)
  • too big to include just for option handling: 322 *.h (44750 lines) + 7 *.cpp (2078 lines)

Why not use tclap/Opag/Options/CmdLine/Anyoption/Argument_helper/...?

  • no reason, writing one is faster than code inspection :-)
  • similarity to Python desired for faster learning curve

Future work

  • nargs > 1?
  • comments?

Example

#include <optparse.h>

#include <iostream>
#include <string>
#include <vector>


int main(int argc, char **argv)
{
    optparse::OptionParser parser =
        optparse::OptionParser().description("just an example");

    parser.add_option("-f", "--file").dest("filename")
          .help("write report to FILE").metavar("FILE");
    parser.add_option("-q", "--quiet")
          .action("store_false")
          .dest("verbose")
          .set_default("1")
          .help("don't print status messages to stdout");

    const optparse::Values options = parser.parse_args(argc, argv);
    const std::vector<std::string> args = parser.args();

    if (options.get("verbose"))
    {
        std::cout << options["filename"] << "\n";
    }
}