Re: [Groff] Re: getopt() as gtroff macro ?

[Werner LEMBERG]

> >> I think this is important and, while I admire what Keith has
> >> done, I wonder if there's any way to get a getopt built into
> >> gtroff?
> >
> > Nice idea.  What exactly do you have in mind?  Can you make syntax
> > suggestions?
> 
> I agree, this would be a nice feature to have.  Perhaps something
> along the lines of the shell's built-in 'getopts' command?
> 
> The main problem I foresee is, how do you implement the call backs
> needed, to allow getopt's caller to handle the optional arguments as
> they are parsed?  This could end up being no simpler than the
> technique I suggested earlier, but it would be great if we can
> identify a viable solution.

What about the following (inspired by Python's getopt module):

  .getopt <prefix> <options> <long options>

Example:

  .de foo
  .  getopt "foox" "ac:" "--all --check="
  .  ...
  ..

The .getopt command would call the functions `<prefix>-<option>', passing
the corresponding values as arguments.  `<prefix>-?' (with <option> as
the argument) is called if <option> is invalid.  Finally, all
non-option arguments are passed to a macro called `<prefix>'.

Calling the above function like this

  .foo -a -c bar --all --check=urgh --xxx arg1 arg2

would consequently call the functions

  .foox-a
  .foox-c bar
  .foox--all
  .foox--check urgh
  .foox-? --xxx
  .foox arg1 arg2

It probably makes sense to provide a .gnu-getopt request also to
reorder the arguments.

Comments, please.


    Werner