For now, this reference is a best-effort document. We strive for validity and completeness, but are not yet there. In the future, the docs and lang teams will work together to figure out how best to do this. Until then, this is a best-effort attempt. If you find something wrong or missing, file an issue or send in a pull request.

Boolean type

The bool type is a datatype which can be either true or false. The boolean type uses one byte of memory. It is used in comparisons and bitwise operations like &, |, and !.

fn main() {
    let x = true;
    let y: bool = false; // with the boolean type annotation

    // Use of booleans in conditional expressions
    if x {
        println!("x is true");