| # Program arguments |
| |
| ## Standard Library |
| |
| The command line arguments can be accessed using `std::env::args`, which |
| returns an iterator that yields a `String` for each argument: |
| |
| ```rust,editable |
| use std::env; |
| |
| fn main() { |
| let args: Vec<String> = env::args().collect(); |
| |
| // The first argument is the path that was used to call the program. |
| println!("My path is {}.", args[0]); |
| |
| // The rest of the arguments are the passed command line parameters. |
| // Call the program like this: |
| // $ ./args arg1 arg2 |
| println!("I got {:?} arguments: {:?}.", args.len() - 1, &args[1..]); |
| } |
| ``` |
| |
| ```shell |
| $ ./args 1 2 3 |
| My path is ./args. |
| I got 3 arguments: ["1", "2", "3"]. |
| ``` |
| |
| ## Crates |
| |
| Alternatively, there are numerous crates that can provide extra functionality |
| when creating command-line applications. The [Rust Cookbook] exhibits best |
| practices on how to use one of the more popular command line argument crates, |
| `clap`. |
| |
| [Rust Cookbook]: https://rust-lang-nursery.github.io/rust-cookbook/cli/arguments.html |
