D Argument Parser

Example

importstd.stdio;import darg;structOptions{    @Option("help","h")    @Help("Prints this help.")    OptionFlag help;    @Option("threads","t")    @Help("Number of threads to use.")size_t threads;    @Argument("file", Multiplicity.zeroOrMore)    @Help("Input files")string[] files;}// Generate the usage and help string at compile time.immutable usage = usageString!Options("example");immutable help = helpString!Options;intmain(string[] args){    Options options;try    {        options = parseArgs!Options(args[1.. $]);    }catch (ArgParseError e)    {        writeln(e.msg);        writeln(usage);return1;    }catch (ArgParseHelp e)    {// Help was requested        writeln(usage);        write(help);return0;    }foreach (f; options.files)    {// Use files    }return0;}

$ ./example --helpUsage: example [--help] [--threads=<ulong>] [file...]Positional arguments: file            Input filesOptional arguments: --help, -h      Prints this help. --threads, -t <ulong>                 Number of threads to use.$ ./example --foobarUnknown option '--foobar'Usage: program [--help] [--threads=<ulong>] [file...]

License