How to accept command line arguments in Rust

Overview

A command line argument is a collection of values or specifiers supplied to the terminal. Therefore, these parameters can change the program’s behavior, as described in the source code. Let's look at Rust's syntax.

Syntax 

    let args: Vec<String> = env::args().collect();
Accept command line arguments in Rust
  • env::args().collect();: This returns the argument passed in the terminal.

Pass an argument in the terminal

We use cargo run to pass an argument through the terminal:

cargo run a b c
Pass an argument in the terminal

Example 

use std::env;
  
fn main() {
    let args: Vec<String> = env::args().collect();
    println!("We got {:?} arguments: {:?}.", args.len()-1, &args[1..]);
}

Explanation

  • Line 1: We use the Rust library, std::env;. It returns an iterator of the command line arguments supplied.
  • Lines 4 and 5: We use env::args().collect();. This returns the argument passed in the terminal and shows the number of arguments.

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