Tries to deserialize the map of values into a struct.

This method should always be called to deserialize a ArgvMap into a struct. All fields of the struct must map to a corresponding key in the ArgvMap. To this end, each member must have a special prefix corresponding to the different kinds of patterns in Docopt. There are three prefixes: flag_, arg_ and cmd_ which respectively correspond to short/long flags, positional arguments and commands.

If a Docopt item has a - in its name, then it is converted to an _.

Example

#[macro_use]
extern crate serde_derive;
use docopt::Docopt;

const USAGE: &'static str = "
Usage: cargo [options] (build | test)
       cargo --help

Options: -v, --verbose
         -h, --help
";

#[derive(Deserialize)]
struct Args {
  cmd_build: bool,
  cmd_test: bool,
  flag_verbose: bool,
  flag_h: bool,
}

let argv = || vec!["cargo", "build", "-v"].into_iter();
let args: Args = Docopt::new(USAGE)
                        .and_then(|d| d.argv(argv()).deserialize())
                        .unwrap_or_else(|e| e.exit());
assert!(args.cmd_build && !args.cmd_test
        && args.flag_verbose && !args.flag_h);

Note that in the above example, flag_h is used but flag_help could also be used. (In fact, both could be used at the same time.)

In this example, only the bool type was used, but any type satisfying the Deserialize trait is valid.

Finds the value corresponding to key and calls as_bool() on it. If the key does not exist, false is returned.

Finds the value corresponding to key and calls as_count() on it. If the key does not exist, 0 is returned.

Finds the value corresponding to key and calls as_str() on it. If the key does not exist, "" is returned.

Finds the value corresponding to key and calls as_vec() on it. If the key does not exist, vec!() is returned.

Return the raw value corresponding to some key.

key should be a string in the traditional Docopt format. e.g., <arg> or --flag.

Return the number of values, not including synonyms.