confusing/
confusing.rs

1//! You can do potentially confusing things if you really-really have to :)
2
3// I want something like this ./binary --arg1 "stuff" subcommand --arg2 "stuff" I want arg1
4// to be at "top level" because it will be used by many sub commands and be mandatory almost always
5// unless arg2 is passed to the subcommand.
6
7// In practice it would be ./binary --token "token" create --org "org" and ./binary create
8// --example where the last case wouldn't need the token because we aren't doing any api calls.
9
10use bpaf::*;
11
12/// this datatype is intended for program consumption, usize field in complex commands
13/// is a shared top level argument
14#[derive(Debug, Clone)]
15enum Command {
16    Simple,
17    Complex1(String, i32),
18    Complex2(String, i16),
19}
20
21/// this datatype is just an intermediate representation,
22/// it exists only to ensure that the final type (Command) can be used without unwraps
23#[derive(Debug, Clone)]
24enum PreCommand {
25    Simple,
26    Complex1(i32),
27    Complex2(i16),
28}
29
30fn main() {
31    let token = long("token")
32        .help("Token used for complex commands")
33        .argument::<String>("TOKEN")
34        .optional();
35
36    // start with defining 3 commands: simple, complex1 and complex2
37    let simple_parser = pure(PreCommand::Simple).to_options();
38    let simple = simple_parser.command("simple");
39
40    let complex1_parser = positional::<i32>("ARG");
41    let complex1 = construct!(PreCommand::Complex1(complex1_parser))
42        .to_options()
43        .descr("This is complex command 1")
44        .command("complex1");
45
46    let complex2_parser = positional::<i16>("ARG");
47
48    let complex2 = construct!(PreCommand::Complex2(complex2_parser))
49        .to_options()
50        .descr("This is complex command 2")
51        .command("complex2");
52
53    // compose then to accept any of those
54    let preparser = construct!([simple, complex1, complex2]);
55
56    // make a parser that accepts optional token and one of incomplete commands
57    // then create complete command or fail
58    let parser = construct!(token, preparser).parse(|(token, cmd)| match cmd {
59        PreCommand::Simple => Ok(Command::Simple),
60        PreCommand::Complex1(a) => match token {
61            Some(token) => Ok(Command::Complex1(token, a)),
62            None => Err("You must specify token to use with --token"),
63        },
64        PreCommand::Complex2(a) => match token {
65            Some(token) => Ok(Command::Complex2(token, a)),
66            None => Err("You must specify token to use with --token"),
67        },
68    });
69
70    let cmd = parser.to_options().run();
71    println!("{:?}", cmd);
72}
confusing/confusing.rs

confusing/
confusing.rs
