blob: a0a986f98307b5949488bcba8043a0818fc514e7 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
|
extern crate clap;
use clap::{App, Arg};
fn main() {
// Once all App settings (including all arguments) have been set, you call get_matches() which
// parses the string provided by the user, and returns all the valid matches to the ones you
// specified.
//
// You can then query the matches struct to get information about how the user ran the program
// at startup.
//
// For this example, let's assume you created an App which accepts three arguments (plus two
// generated by clap), a flag to display debugging information triggered with "-d" or
// "--debug" as well as an option argument which specifies a custom configuration file to use
// triggered with "-c file" or "--config file" or "--config=file" and finally a positional
// argument which is the input file we want to work with, this will be the only required
// argument.
let matches = App::new("MyApp")
.about("Parses an input file to do awesome things")
.version("1.0")
.author("Kevin K. <kbknapp@gmail.com>")
.arg(Arg::with_name("debug")
.help("turn on debugging information")
.short("d")
.long("debug"))
.arg(Arg::with_name("config")
.help("sets the config file to use")
.short("c")
.long("config"))
.arg(Arg::with_name("input")
.help("the input file to use")
.index(1)
.required(true))
.get_matches();
// We can find out whether or not debugging was turned on
if matches.is_present("debug") {
println!("Debugging is turned on");
}
// If we wanted to do some custom initialization based off some configuration file
// provided by the user, we could get the file (A string of the file)
if let Some(file) = matches.value_of("config") {
println!("Using config file: {}", file);
}
// Because "input" is required we can safely call unwrap() because had the user NOT
// specified a value, clap would have explained the error the user, and exited.
println!("Doing real work with file: {}", matches.value_of("input").unwrap() );
// Continued program logic goes here...
}
|
