Re: Argument parser

[Yoshinori K. Okuji]

Some random ideas about your code:

* What is ARG_TYPE_CHAR? In what case would it be useful?
* ARG_TYPE_INT uses strtoul... It sounds odd, because I myself think
  of _signed_ int when seeing just "int".
* It seems not to support concatenating multiple single-character
  options (e.g. "-zxvf").
* Does it support normal arguments, like the "foobar" in "ls foobar"?
* shortarg should have the type int instead of char.

Also, I'd like to suggest an additional idea. Basically, my goal is to 
reduce code which must be written for each command. So your parser 
should be integrated with the command-line engine fully, so that your 
parser is invoked automatically by the engine, instead of calling your 
parser explicitly from a function of each command.

For example, you can extend the pupa_register_command to accept 
information on options of a registered command. Then, probably it is 
also necessary to change the arguments to a callback function for a 
command.

Please see this psuedo code:

static struct pupa_option_information = 
{
  // The default is 1.
  { 'c', "count", "1", "Specify how many times ...", PUPA_TYPE_UINT },
  { 0 }
}
options;

pupa_cmd_hello(opts, args)
{
  // 1 is the default value.
  count = pupa_atoi(pupa_parser_get_option (opts, 'c'));
  // Say it now!
  while (count-- > 0)
    pupa_printf ("Hello World\n");
}

init()
{
  pupa_register_command ("hello", pupa_cmd_hello, &options);
}


I'm sorry that I didn't reply very soon. In my town, we had a big 
festival, so I was enjoying with another thing (I was about dying 
actually, though.)

Okuji