1For more on creating a custom subcommand, see [the cargo
2book](https://doc.rust-lang.org/cargo/reference/external-tools.html#custom-subcommands).
3The crate [`clap-cargo`](https://github.com/crate-ci/clap-cargo) can help in
4mimicking cargo's interface.
5
6The help looks like:
7```console
8$ cargo-example-derive --help
9cargo
10
11USAGE:
12    cargo <SUBCOMMAND>
13
14OPTIONS:
15    -h, --help    Print help information
16
17SUBCOMMANDS:
18    example-derive    A simple to use, efficient, and full-featured Command Line Argument Parser
19    help              Print this message or the help of the given subcommand(s)
20
21$ cargo-example-derive example-derive --help
22cargo-example-derive [..]
23A simple to use, efficient, and full-featured Command Line Argument Parser
24
25USAGE:
26    cargo example-derive [OPTIONS]
27
28OPTIONS:
29    -h, --help                             Print help information
30        --manifest-path <MANIFEST_PATH>
31    -V, --version                          Print version information
32
33```
34
35Then to directly invoke the command, run:
36```console
37$ cargo-example-derive example-derive
38None
39
40$ cargo-example-derive example-derive --manifest-path Cargo.toml
41Some("Cargo.toml")
42
43```
44