How to: println in JavaScript

Outputting to your shell or terminal to inform the user of the outcome of a program or valuable debugging information is an essential of every programming language.

Rust

In rust we can use the println! macro to write to output strings and variables.

fn main() {
  println!("Hello World!");
  println!("My name is {}", "Jonathan");
  println!("NOT true is {}", !true);
}

If we want to log the shape of a struct with its values we need to use a different placeholder in our log statement:

#![allow(unused)]
fn main() {
  #[derive(Debug)]
  struct Point {
    x: i32,
    y: i32,
  }

  let origin = Point { x: 5, y: 13 };

  println!("point debug: {origin:#?}")
}

JavaScript

In JavaScript console.log will print to the browser console or your shell where node.js is running your file:

// strings
console.log('Hello World!');
// multiple parameters
console.log('Hello', 'World!', 666);