Separated argument parsing for serve subcommand.

[maccoda]

Hopefully this can address the fourth point on #458. I wasn't sure if the struct notion for passing the arguments through was a good idea. Let me know. Also because of this to pass the struct into the closures it would need to implement Copy but this isn't simply derived as PathBuf does not implement it, hence the weird assignment of the variables before the closures. If there is a better way of handling this I would love to know, not entirely happy with that being the best option.

Thanks!

[Michael-F-Bryan]

I was thinking a better solution overall would be to change argument parsing to structopt, that way we're cleaning up all the subcommands and not just one. This is essentially just a custom derive around clap which will configure a clap argument parser from your structures and ensure they get filled appropriately.

I've used structopt loads and find it avoids a lot of the annoying boilerplate associated with writing the clap parser and your own parse_args() function.

In this case we'd just have a top level enum containing all the subcommands and the arguments they expect.

For example:

#[derive(Debug, Clone, StructOpt)]
pub enum Command {
  #[structopt(name = "build", about = "Compile the document")]
  Build {
    #[structopt(short = "o", long = "short", help = "Open the compiled document")]
    open: bool,
  }
  #[structopt(name = "serve")]
  Serve {
    #[structopt(help = "The book's root directory", default_value = "."_]
    book_dir: PathBuf,
  }
  ...
}

[maccoda]

@Michael-F-Bryan I thought there must have been something like that!! I will look into that one and have another go at it!

[maccoda]

Hi @Michael-F-Bryan I think I have managed to get this one back in sync and hopefully ready to take. Let me know if I should change anything else. Thanks!