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+extern crate clap;
+
+use clap::{App, Arg, SubCommand};
+
+fn main() {
+
+ // SubCommands function exactly like sub-Apps, because that's exactly what they are. Each
+ // instance of a SubCommand can have it's own version, author(s), Args, and even it's own
+ // subcommands.
+ //
+ // # Help and Version
+ // Just like Apps, each subcommand will get it's own "help" and "version" flags automatically
+ // generated. Also, like Apps, you can override "-V" or "-h" safely and still get "--help" and
+ // "--version" auto generated.
+ //
+ // NOTE: If you specify a subcommand for your App, clap will also autogenerate a "help"
+ // subcommand along with "-h" and "--help" (applies to sub-subcommands as well).
+ //
+ // Just like arg() and args(), subcommands can be specified one at a time via subcommand() or
+ // multiple ones at once with a Vec<SubCommand> provided to subcommands().
+ let matches = App::new("MyApp")
+ // Normal App and Arg configuration goes here...
+
+ // In the following example assume we wanted an application which
+ // supported an "add" subcommand, this "add" subcommand also took
+ // one positional argument of a file to add:
+ .subcommand(SubCommand::with_name("add") // The name we call argument with
+ .about("Adds files to myapp") // The message displayed in "myapp -h"
+ // or "myapp help"
+ .version("0.1") // Subcommands can have independent version
+ .author("Kevin K.") // And authors
+ .arg(Arg::with_name("input") // And their own arguments
+ .help("the file to add")
+ .index(1)
+ .required(true)))
+ .get_matches();
+
+ // You can check if a subcommand was used like normal
+ if matches.is_present("add") {
+ println!("'myapp add' was run.");
+ }
+
+ // You can get the independent subcommand matches (which function exactly like App matches)
+ if let Some(matches) = matches.subcommand_matches("add") {
+ // Safe to use unwrap() because of the required() option
+ println!("Adding file: {}", matches.value_of("input").unwrap());
+ }
+
+ // You can also match on a subcommand's name
+ match matches.subcommand_name() {
+ Some("add") => println!("'myapp add' was used"),
+ None => println!("No subcommand was used"),
+ _ => println!("Some other subcommand was used"),
+ }
+
+ // Continued program logic goes here...
+}