mirror of
https://github.com/clap-rs/clap
synced 2024-11-14 00:27:13 +00:00
71 lines
4 KiB
Rust
71 lines
4 KiB
Rust
extern crate clap;
|
|
|
|
use clap::{App, Arg};
|
|
|
|
fn main() {
|
|
|
|
// Option arguments are those that take an additional value, such as "-c value". In clap they
|
|
// support three types of specification, those with short() as "-o some", or those with long()
|
|
// as "--option value" or "--option=value"
|
|
//
|
|
// Options also support a multiple setting, which is discussed in the example below.
|
|
let matches = App::new("MyApp")
|
|
// Regular App configuration goes here...
|
|
|
|
// Assume we an application that accepts an input file via the "-i file"
|
|
// or the "--input file" (as wel as "--input=file").
|
|
// Below every setting supported by option arguments is discussed.
|
|
// NOTE: You DO NOT need to specify each setting, only those which apply
|
|
// to your particular case.
|
|
.arg(Arg::with_name("input")
|
|
.help("the input file to use") // Displayed when showing help info
|
|
.takes_value(true) // MUST be set to true in order to be an "option" argument
|
|
.short("i") // This argument is triggered with "-i"
|
|
.long("input") // This argument is triggered with "--input"
|
|
.multiple(true) // Set to true if you wish to allow multiple occurrences
|
|
// such as "-i file -i other_file -i third_file"
|
|
.required(true) // By default this argument MUST be present
|
|
// NOTE: mutual exclusions take precedence over
|
|
// required arguments
|
|
.requires("config") // Says, "If the user uses "input", they MUST
|
|
// also use this other 'config' arg too"
|
|
// Can also specifiy a list using
|
|
// requires_all(Vec<&str>)
|
|
.conflicts_with("output") // Opposite of requires(), says "if the
|
|
// user uses -a, they CANNOT use 'output'"
|
|
// also has a conflicts_with_all(Vec<&str>)
|
|
)
|
|
// NOTE: In order to compile this example, comment out conflicts_with()
|
|
// and requires() because we have not defined an "output" or "config"
|
|
// argument.
|
|
.get_matches();
|
|
|
|
// We can find out whether or not "input" was used
|
|
if matches.is_present("input") {
|
|
println!("An input file was specified");
|
|
}
|
|
|
|
// We can also get the value for "input"
|
|
//
|
|
// NOTE: If we specified multiple(), this will only return the _FIRST_
|
|
// occurrence
|
|
if let Some(ref in_file) = matches.value_of("input") {
|
|
println!("An input file: {}", in_file);
|
|
}
|
|
|
|
// If we specified the multiple() setting we can get all the values
|
|
if let Some(ref in_v) = matches.values_of("input") {
|
|
for in_file in in_v.iter() {
|
|
println!("An input file: {}", in_file);
|
|
}
|
|
}
|
|
|
|
// We can see how many times the option was used with the occurrences_of() method
|
|
//
|
|
// NOTE: Just like with flags, if we did not specify the multiple() setting this will only
|
|
// return 1 no matter how many times the argument was used (unless it wasn't used at all, in
|
|
// in which case 0 is returned)
|
|
println!("The \"input\" argument was used {} times", matches.occurrences_of("input"));
|
|
|
|
// Continued program logic goes here...
|
|
}
|