Comments and Logging

Comments

Comments in Sway start with two slashes and continue until the end of the line. For comments that extend beyond a single line, you'll need to include // on each line.

// hello world
// let's make a couple of lines
// commented.

You can also place comments at the ends of lines containing code.

fn main() {
    let baz = 8; // Eight is a lucky number
}

You can also do block comments

fn main() {
    /*
    You can write on multiple lines
    like this if you want
    */
    let baz = 8;
}

Logging

To log integers, you can use the log_u64, log_u32, log_u16, or log_u8 functions from the standard library.

use std::chain::log_u64;

fn main() {
    let baz = 8;
    log_u64(baz);
}

Note that you cannot log arbitrary structs yet because we do not yet support serialization.